Frac manifold and systems

ABSTRACT

Missile flow lines are incorporated into frac manifolds, especially trailered or skidded frac manifolds. The missiles manifold the discharge from a plurality of pumps and comprise at least two junction fittings joined by spooled pipe. The junction fittings comprise a body having a primary bore and at least two feed bores. The intersections of the feed bores with the primary bore are offset axially from each other along the primary bore. The junction fittings are joined by flange unions to at least one spooled pipe such a that the junction fittings and spooled pipe form a conduit including the primary bores. A discharge line from a pump may be joined to each feed union face of the junction fittings by a flange union. Thus, the discharge from the pumps may be manifolded into the conduit.

FIELD OF THE INVENTION

The present invention relates generally to fluid transportation systemsand flow lines used in those systems, and especially to frac manifolds,flow lines, and flowline components used to convey abrasive, corrosivefluids under high pressure as are common, for example, in the oil andgas industry.

BACKGROUND OF THE INVENTION

Hydrocarbons, such as oil and gas, may be recovered from various typesof subsurface geological formations. The formations typically consist ofa porous layer, such as limestone and sands, overlaid by a nonporouslayer. Hydrocarbons cannot rise through the nonporous layer. Thus, theporous layer forms a reservoir, that is, a volume in which hydrocarbonsaccumulate. A well is drilled through the earth until the hydrocarbonbearing formation is reached. Hydrocarbons then are able to flow fromthe porous formation into the well.

In what is perhaps the most basic form of rotary drilling methods, adrill bit is attached to a series of pipe sections or “joints” referredto as a drill string. The drill string is suspended from a derrick androtated by a motor in the derrick. A drilling fluid or “mud” is pumpeddown the drill string, through the bit, and into the bore of the well.This fluid serves to lubricate the bit. The drilling mud also carriescuttings from the drilling process back to the surface as it travels upthe wellbore. As the drilling progresses downward, the drill string isextended by adding more joints of pipe.

When the drill bit has reached the desired depth, larger diameter pipes,or casing, are placed in the well and cemented in place to prevent thesides of the borehole from caving in. The well may be extended bydrilling additional sections and installing large, but somewhat smallerpipes, or liners. The liners also are typically cemented in the bore.The liner may include valves, or it may then be perforated. In eitherevent, openings in the liner are created through which oil can enter thecased well. Production tubing, valves, and other equipment are installedin the well so that the hydrocarbons may flow in a controlled mannerfrom the formation, into the lined well bore, and through the productiontubing up to the surface for storage or transport.

Hydrocarbons, however, are not always able to flow easily from aformation to a well. Some subsurface formations, such as sandstone, arevery porous. Hydrocarbons can flow easily from the formation into awell. Other formations, however, such as shale rock, limestone, and coalbeds, are only minimally porous. The formation may contain largequantities of hydrocarbons, but production through a conventional wellmay not be commercially practical because hydrocarbons flow though theformation and collect in the well at very low rates. The industry,therefore, relies on various techniques for improving the well andstimulating production from formations. In particular, varioustechniques are available for increasing production from formations whichare relatively nonporous.

Perhaps the most important stimulation technique is the combination ofhorizontal wellbores and hydraulic fracturing. A well will be drilledvertically until it approaches a formation. It then will be diverted,and drilled in a more or less horizontal direction, so that the boreholeextends along the formation instead of passing through it. More of theformation is exposed to the borehole, and the average distancehydrocarbons must flow to reach the well is decreased. Fractures thenare created in the formation which will allow hydrocarbons to flow moreeasily from the formation.

Fracturing a formation is accomplished by pumping fluid, most commonlywater, into the well at high pressure and flow rates. Proppants, such asgrains of sand, ceramic or other particulates, usually are added to thefluid along with gelling agents to create a slurry. The slurry is forcedinto the formation at rates faster than can be accepted by the existingpores, fractures, faults, vugs, caverns, or other spaces within theformation. Pressure builds rapidly to the point where the formationfails and begins to fracture. Continued pumping of fluid into theformation will tend to cause the initial fractures to widen and extendfurther away from the wellbore, creating flow paths to the well. Theproppant serves to prevent fractures from closing when pumping isstopped.

A formation rarely will be fractured all at once. It typically will befractured in many different locations or zones and in many differentstages. Fluids will be pumped into the well to fracture the formation ina first zone. Typically, the first zone will be at the bottom or “toe”of the well. After the initial zone is fractured, pumping is stopped,and a plug is installed or otherwise established in the liner at a pointabove the fractured zone. Pumping is resumed, and fluids are pumped intothe well to fracture the formation in a second zone located above theplug. That process is repeated for zones further up the formation untilthe formation has been completely fractured.

Once the well is fractured, large quantities of water and sand that wereinjected into the formation eventually must be allowed to flow out ofthe well. The water and sand will be separated from hydrocarbonsproduced by the well to protect downstream equipment from damage andcorrosion. The production stream also may require additional processingto neutralize corrosive agents in the stream.

Systems for successfully completing a fracturing operation, therefore,are extensive and complex, as may be appreciated from FIG. 1. FIG. 1illustrates schematically a common, conventional frac system. Water fromtanks 1 and gelling agents dispensed by a chemical unit 2 are mixed in ahydration unit 3. The discharge from hydration unit 3, along with sandcarried on conveyors 4 from sand tanks 5 is fed into a blending unit 6.Blender 6 mixes the gelled water and sand into a slurry. The slurry isdischarged through low-pressure hoses 7 which convey it into two or morelow-pressure lines 8 in a frac manifold 9. The low-pressure lines 8 infrac manifold 9 feed the slurry to an array of pumps 10, perhaps as manyas a dozen or more, through low-pressure “suction” hoses 11.

Pumps 10 take the slurry and discharge it at high pressure throughindividual high-pressure “discharge” lines 12 into two or morehigh-pressure lines or “missiles” 13 on frac manifold 9. Missiles 13flow together, i.e., they are manifolded on frac manifold 9. Severalhigh-pressure flow lines 14 run from the manifolded missiles 13 to a“goat head” 15. Goat head 15 delivers the slurry into a “zipper”manifold 16 (also referred to by some as a “frac manifold”). Zippermanifold 16 allows the slurry to be selectively diverted to, forexample, one of two well heads 17 which control flow into and out of thewell. Once fracturing is complete, flow back from the fracturingoperation discharges into a flowback manifold 18 which leads intoflowback tanks 19.

Frac systems are viewed as having “low-pressure” and “high-pressure”sides or, more simply, as having low sides and high sides. The low sideincludes the components upstream of the inlet of pumps 10, e.g., watertanks 1, hydration unit 3, blending unit 6, and the low-pressure lines 8of frac manifold 9, which operate under relatively low pressures. Thehigh side includes all the components downstream of the dischargeoutlets of pumps 10, e.g., the high-pressure missiles 13 of fracmanifold 9 and flow lines 14 running to goat head 15, which operateunder relatively high pressures.

The larger units of a frac system are transported to a well site onskids, trailers, or trucks and then connected by one kind of conduit oranother. The conduits on the low-pressure side typically will beflexible hoses, such as blender hoses 7 and suction hoses 11. On theother hand, flow lines 14 running to goat head 15 and otherhigh-pressure side conduits will be subject to extremely high pressures.They must be more rugged. They also typically will be assembled on site.

Flow lines 14 and other portions of the high-side that are assembled onsite are made up from a variety of components often referred to as “fraciron,” “flow iron,” or “ground iron.” Such components include sectionsof straight steel pipe, such as pup joints. They also include variousfittings, such as tees, crosses, laterals, and wyes, which providejunctions at which flow is split or combined. In addition to junctionfittings, flowline components include fittings which are used to alterthe course of a flow line. Such directional fittings include elbows andswivel joints. High-pressure flow lines also incorporate gauges andother monitoring equipment, as well as control devices such as shut off,plug, check, throttle, pressure release, butterfly, and choke valves.

Because frac systems are required at a site for a relatively shortperiod of time, frac iron components often are joined by unions. Unionsallow the components to be connected (“made up”) and disconnected(“broken down”) relatively quickly. The three types of unions commonlyused in frac systems are hammer (or “Weco®”) unions, clamp (or“Greyloc®”) unions, and flange unions. Though spoken of in terms thatmay imply they are discreet components, unions are actuallyinterconnected subassemblies of the components joined by the union. Amale sub will be on one component, and a mating female sub will be onthe other. The subs then will be connected to each other to provide theunion.

Flange unions may be made up and broken down with relative ease. Theirbasic design is robust and reliable, and like other flowline components,they are manufactured from heavy, high tensile steel. Thus, they havebeen adapted for low pressure (1,000 to 2,000 psi), medium pressure(2,000 to 4,000 psi), and high pressure service (6,000 to 20,000 psi).Moreover, unlike hammer and clamp unions, flange unions do not rely onseals that are exposed to fluids passing through the union.

Flange unions, as their name implies, typically provide a connectionbetween two flanged components, such as spooled pipe or simply “spools.”Spooled pipe is provided with annular flanges extending radially outwardfrom each end, thus giving the pipe the appearance of a spool. Theflanges provide flat surfaces or faces which allow two spools to mate attheir flanges. The flanges also are provided with a number of boltholes. The holes are arranged angularly around the flange. Thus, spooledpipes may be connected by bolting mating flanges together. Each flangewill have an annular groove running concentrically around the pipeopening. An annular metal seal is carried in the grooves to provide aseal between the flanges.

Though not entirely apparent from the schematic representation of FIG.1, it will be appreciated that conventional frac systems are assembledfrom a very large number of individual components. Assembly of so manyunits on site can be time consuming, expensive, and hazardous. Thus,some components of a frac system are assembled off site on skids ortrailers and transported as a unit to the well site.

Commonly skidded units include not only process units, such as blender 6and pumps 10, but also flow units. Frac manifold 9, for example, is anassembly of pipes, junctions, valves, and other flowline components thattypically are assembled off-site. Collectively, they provide a flow unitthat manifolds, distributes, and controls discharge from pumps 10.Zipper manifold 16 is another flow unit that at times is assembledoff-site from separate flowline components. Zipper manifold 16 receivesflow from flow lines 14 and selectively distributes it to multiple wellheads 17. Such units may have been assembled on site in the past. Byskidding them, or mounting them on a trailer, assembly time at the wellsite is greatly reduced. Moreover, the components typically may beassembled more efficiently and reliably, and may be tested more easilyin an off-site facility.

At the same time, because they are transported as a unit, trailered andskidded units are subject to spatial constraints that typically are notso severe as on site. Frac trailers, for example, have multiple flowlines incorporating a large number of flowline components, both on thehigh-pressure side and the low-pressure side. Multiple flow lines aremanifolded. Providing all of those flow lines and manifolds on a trailerwhich meets highway regulatory requirements often results in a complex,cluttered design which may be difficult or impossible to service onsite.

A well head also is fixed. Trailered and skidded units can be quitelarge, heavy, and moveable only with difficulty and limited precision.Flow lines, therefore, necessarily incorporate directional fittings,such as elbows and swivel joints, which allow its course to be alteredto accommodate two unaligned units.

Elbow joints are simply curved sections of pipe which provide, forexample, a 90° turn in a line. Swivel joints most commonly are anassembly of elbow conduits, usually three, with rotatable joints. Thejoints are packed with bearings, typically ball bearings, which allowthe elbow conduits to rotate relative to each other. Swivel joints,therefore, can accommodate varying degrees of misalignment between thecomponents which they connect and can provide considerable flexibilityin assembling a flow line between essentially immovable points.

Though much less common, swivel flanges also are used to provide similarflexibility. Swivel flanges have a flange mounted on a hub. The hub isformed, for example, at one end of a length of pipe. Bearings, usuallyroller bearings, are packed around the hub, and the flange can rotatearound the hub on the bearings. When joined together, a pair ofswivel-flanged pipes and a pair of elbow joints, like swivel joints, canaccommodate varying alignments between components to be joined.Consequently, it is rare, if ever, that the high-side of a frac systemdoes not incorporate at least one or, more likely, multiple swiveljoints or swivel flanges.

The large number of individual components in a frac system is compoundedby the fact that most conventional frac systems incorporate a largenumber of relatively small flow lines, typically 3″ and 4″ flow lines.In part that is unavoidable. The pumps cannot be deployed in series andthe flow lines carrying their individual discharges must be manifolded.Likewise, if multiple wells are to be serviced by the same array ofpumps without assembling and disassembling flow lines, at some pointtheir collective discharge must be split or directed into differentflowline segments.

On the other hand, multiple flow lines in many instances represent adesign choice. That is, certain flow rates and pressures will berequired to fracture a particular well. Those flow rates and pressureswill determine the number and capacities of the pumps. The high-pressureside then is designed to deliver the required flow rate withoutexceeding a maximum or “erosional” flow velocity, typically about40′/sec, through the system. Additional flow lines often are added toprovide higher flow rates into a well. The net result is that a frackingsystem often is so complicated that it resembles to the uninitiated atangled mass of spaghetti.

Efforts have been made to simplify the flow line by incorporating fewersegments. For example, the conventional frac system illustrated in FIG.1 includes four flow lines 14 running from the high-pressure lines 13 offrac manifold 9 to goat head 15. Some frac systems now employ a single,larger flowline segment running in place of four smaller lines. A singlelarger flow line will incorporate fewer parts and, therefore, fewerpotential leak points. Both in terms of direct material and labor costs,a single larger flow line often will be less expensive than multiplesmaller lines.

Frac jobs also have become more extensive, both in terms of thepressures required to fracture a formation and the time required tocomplete all stages of an operation. Prior to horizontal drilling, atypical vertical well might require fracturing in only one, two or threezones at pressures usually well below 10,000 psi. Fracturing ahorizontal well, however, may require fracturing in 20 or more zones.Horizontal wells in shale formations such as the Eagle Ford shale inSouth Texas typically require fracturing pressures of at least 9,000 psiand 6 to 8 hours or more of pumping. Horizontal wells in the Haynesvilleshale in northeast Texas and northwest Louisiana require pressuresaround 13,500 psi. Pumping may continue near continuously—at flow ratesof 2 to 3 thousand gallons per minute (gpm)—for several days beforefracturing is complete.

Moreover, at least in the early stages of production, the flow backafter fracturing also will be at high pressure and flow rates. Theinitial production stream from a fractured well flows at pressures inthe range of from 3,000 to 5,000 psi, and more and more commonly up to10,000 psi. The flow rates can approach a million cubic feet per hour ormore.

Given the high number of components, leaking at unions is always aconcern in frac systems. The unions may not always be assembledproperly. Even when assembled to specification, however, such issues areexacerbated by the extremely high pressures and flow rates through thesystem. Many unions also incorporate elastomeric seals which are exposedto flow through the conduit and are particularly susceptible to leaking.

Moreover, the abrasive and corrosive nature of the slurry flowingthrough a frac system not only will accelerate deterioration of exposedelastomeric seals, it can rapidly erode and weaken conduit walls. Flowthrough relatively long straight sections of pipe is relatively laminar.Flow through other areas, however, such as unions where exposed sealsoften are present, may be quite turbulent. Erosion also is a moresignificant issue where a flow line changes direction. Flow will moredirectly impact conduit walls, causing more abrasion than that causedsimply by fluid passing over the walls. The flowlines in conventionalfrac manifolds, in particular, typically have numerous, relatively sharpturns which are susceptible to damage.

The high pressures and flow rates of fluid flowing through the systemalso typically will create vibration throughout the system. Thevibration can be profound. It tends to create bending stress through thesystem which can exacerbate leakage, especially at unions. The effectsof accumulated stress over periods of time also can accelerate corrosionand erosion of flowline components.

Flowline components also are quite expensive. Swivel joints inparticular are expensive and often comprise the single largest partexpense of a high-side flow line. At the same time, the general issuesdiscussed above seem to be more focused in respect to swivel joints.Swivel joints often incorporate exposed elastomeric seals. Flow throughswivel joints is relatively turbulent. Because they incorporaterotatable joints and connect unaligned components, swivel joints areparticularly susceptible to bending stress caused by vibration in theflow line. They also may be disassembled on site for service and may notalways be reassembled to specification.

Any failure of flowline components on site may interrupt fracturing,potentially reducing its effectiveness and inevitably increasing theamount of time required to complete the operation. Catastrophic failuremay endanger service personnel. Thus, flowline components must becertified and periodically recertified as complying with ratedspecifications. The harsh operating conditions to which they areexposed, however, may cause damage or weakening of the components whichis difficult to detect, such as fatigue stress and microscopicfracturing. Thus, flow iron typically must be disassembled and inspectedoff-site.

In any event, the cost of repeatedly recertifying or replacingcomponents can add significantly to operating costs of the system. Thus,high-pressure flowline components are required to endure extremelyabrasive fluids flowing at extremely high pressures and rates and,hopefully, to do so over an extended service life.

Finally, even frac iron components which may be viewed as relativelysmall, such as a flanged spool or a junction fitting, are extremelyheavy. They must be handled by mechanical lifts, either in the shop oron a site. Positioning the components to allow their unions to be madeup or broken down can be difficult and can create a risk of injury toworkers.

The statements in this section are intended to provide backgroundinformation related to the invention disclosed and claimed herein. Suchinformation may or may not constitute prior art. It will be appreciatedfrom the foregoing, however, that there remains a need for new andimproved frac manifolds and high-pressure flow lines and flowlinecomponents. Likewise, there is a need for new and improved methods ofassembling flow lines and fluid transportation systems. Suchdisadvantages and others inherent in the prior art are addressed byvarious aspects and embodiments of the subject invention.

SUMMARY OF THE INVENTION

The subject invention, in its various aspects and embodiments, relatesgenerally to fluid transportation systems and flow lines used in thosesystems and encompasses various embodiments and aspects, some of whichare specifically described and illustrated herein. One broad embodimentprovides for missile flow lines which may be incorporated into fracmanifolds, especially trailered or skidded frac manifolds. The missilesmanifold the discharge from a plurality of pumps and comprise at leasttwo junction fittings joined by spooled pipe. The junction fittingscomprise a body having a primary bore and at least two feed bores. Theprimary bore extends axially through the body between first and secondprimary faces. The primary faces are union faces adapted for connectionto a flowline component by a flange union. The feed bores extendradially through the body from a feed face to an intersection with theprimary bore. The feed faces also are union faces adapted for connectionto a flowline component by a flange union. The intersections of the feedbores with the primary bore are offset axially from each other along theprimary bore. The junction fittings are joined by flange unions to atleast one spooled pipe such that the junction fittings and spooled pipeform a conduit including the primary bores. A discharge line from a pumpmay be joined to each feed union face of the junction fittings by aflange union. Thus, the discharge from the pumps may be manifolded intothe conduit.

Additional embodiments provide such missiles where the ratio of theminimum width of the body of the junction fitting to the maximum widthof the primary bore in the junction fitting is at least about 3 to 2,preferably at least about 2 to 1, and more preferably at least bout 3to 1. Similar embodiments provide missiles where the junction fittingshave a generally cylindrical body and the ratio of the diameter of thefitting body to the diameter of the primary bore is at least about 3 to2, preferably at least about 2 to 1, and more preferably at least about3 to 1.

Other aspects and embodiments provide such missiles where at least onefeed bore forms a long-sweep curve into the primary bore, preferably along-sweep curve having a sweep ratio of from about 1.25 to about 8.Still other embodiments provide such missiles where the feed bores arestraight-line bores.

In other aspects, the missiles may have feed bores intersecting with theprimary bore at an angle of approximately 900, or at an interior angleof about 45°, or at an interior angle of from about 15° to about 60°.

Still other embodiments provide such missiles where the missile conduithas an inner diameter about equal to or greater than at least about 5inches or at least about 7 inches.

Yet other embodiments provide such missiles where the junction fittinghas a weep port extending from the primary faces or the feed faces tothe exterior of the junction fitting.

Additional embodiments provide missiles having a ported flange joined tothe upstream-most junction fitting of the missile. Other embodimentsprovide missiles having a flush-port assembly joined to the upstream endjunction fitting and comprising a ported flange having a union sub.

Additional embodiments provide such missiles where the fitting body hasa generally cylindrical configuration, where the body is machined from acylindrical bar, where the fitting body has a generally polyhedralconfiguration, or where the fitting body has a generally prismaticconfiguration.

Still other embodiments provide frac manifolds which are mounted on askid or trailer and comprise various embodiments of the novel missiles,preferably a single such missile, and at least one low-pressure suctionline. Other embodiments include high-pressure fluid transportationsystem comprising various embodiments of the novel missiles. Embodimentsalso include methods of assembling a high-pressure fluid transportationsystem where the method comprises assembling a novel missile into thesystem by connecting it to a flowline component by a flange union.

In other aspects and embodiments, the invention provides fluidtransportation systems for fracturing a well. The systems comprise amissile adapted to manifold the discharge from a plurality of pumps. Aflow line is connected to the missile. A wellhead assembly is connectedto the flowline. A liner extends into the well and is in fluidcommunication with the wellhead assembly. The inner diameter of themissile and the flow line have diameters about equal to or greater thanthe inner diameter of the liner.

Other embodiments provide such frac systems where the liner has an innerdiameter about equal to or greater than 5 inches, or where the line hasan inner diameter about equal to or greater than 7 inches.

Additional embodiments provide such frac systems where the missile has aflush port in its upstream end allowing fluid to be introduced into themissile.

In still other aspects and embodiments, the invention provides fracmanifolds comprising a frame. The frame comprises two lateral beamsjoined by cross-members. A single missile adapted to manifold thedischarge from a plurality of pumps is mounted on the frame.

Further embodiments provide such frac manifolds where at least a portionof the frame is adapted to rest on a site pad or where at least aportion of the lateral beams rest on the site pad.

Yet other embodiments provide such frac manifolds where the lateralbeams are at least as long as the missile.

In other embodiments of the frac manifold, the missile is coupled toboth lateral beams. In other embodiments the missile is coupled to theframe by a plurality of mounts. The missiles are coupled to the mounts,and the mounts are coupled to the frame.

Additional embodiments provide such frac manifolds where the missilecomprises junction fittings having a generally cylindrical body. Themounts comprise a pedestal and a cradle. The mounts are coupled to theframe. The cradles are adapted to receive the junction fittings and torestrict transverse movement of the junction fittings.

In other embodiments the length of the cradle is at least about 50% or,preferably at least about 80% of the length of the junction fittings.Other embodiments provide such frac manifolds where the pedestal of themounts extends at least partially over both the lateral beams and iscoupled thereto.

Additional embodiments provide such frac manifolds where the mountscomprise a base extending horizontally between said lateral beams and astandard supporting said missile. The standard extends across the baseand at least partially across the lateral beams. In other embodimentsthe pedestal comprises a base that extends horizontally between thelateral beams and a standard. The standard supports the cradle andextends across the base and at least partially across the lateral beams.

In still other embodiments the frame is incorporated into a trailer. Inother embodiments the frame comprises a plurality of verticallyadjustable, jackup legs adapted to raise and lower the frame. Yet otherembodiments provide such frac manifolds where the jackup legs comprise avertical lifter and where the vertical lifter is attached to ahorizontal extender.

Other aspects and embodiments of the invention provide frac manifoldmodules. The manifold modules comprise a frame. The frame supports amissile adapted to manifold the discharge from a plurality of pumps aswell as a suction line or a pair of suction lines adapted to distributeflow to the plurality of pumps. The manifold module lacks a suctionmanifold distributing flow to the suction lines.

Additional embodiments provide such manifold modules where the missileis adapted for connection at its downstream end to a flow line or to amissile on a first other frac manifold. The missile is adapted forconnection at its upstream end to a missile on a second other manifold.

Other embodiments provide frac manifold systems. The manifold systemscomprise a first and second manifold module. Each manifold modulecomprises a frame and a single missile providing a straight flow lineadapted to manifold the discharge from a plurality of pumps. The missileon the first module is joined to the missile on the second module. Otherembodiments provide such manifold systems where the missiles on thefirst and second modules are aligned to provide a straight flow line.

Still other embodiments provide such manifold systems where the firstand second modules comprise a pair of suction lines. The first modulecomprises a suction manifold adapted to distribute flow to the suctionlines. The second module lacks a suction manifold. The suction lines onthe first module are connected to the suction lines on the secondmodule.

Additional embodiments provide such manifold systems where at least oneof the manifold modules comprise levelers adapted to align the missiles.Other embodiments provide such modules which comprise a plurality ofvertically adjustable, jackup legs adapted to raise and lower the frame.The jackup legs may comprise a vertical lifter. The vertical lifter maybe attached to a horizontal extender.

In other aspects and embodiments, the invention provides methods fortransporting frac manifolds to and from a site. The method comprisesloading the frac manifold on a trailer and transporting the trailer to asite. Jackup legs on the frac manifold then are actuated to elevate thefrac manifold above the trailer. The trailer then is moved out fromunder the frac manifold.

In other aspects and embodiments, the invention provides for flow lineassemblies mounted on a frame. The assemblies comprise a flow linehaving a plurality of components joined by unions along a common axis.The unions allow the components to be made up and broken down. Thecomponents are releasably coupled to the frame to restrict movementalong the axis. When they are uncoupled from the frame, they are adaptedto translate relative to the frame along the axis. The assemblies alsocomprise a shifter. The shifter is adapted for selective coupling to thecomponents and for movement along the axis. The shifter may be actuatedto shift a first component relative to a second component along theaxis. The first component is uncoupled from the frame and coupled to theshifter. The shifter then is actuated.

Other embodiments provide such assemblies where the flow line is amissile and the components comprise cross junction fittings. In otherembodiments the components are coupled to the frame by a mount. Thecomponents are fixedly coupled to the mount, and the mounts arereleasably coupled to the frame. The shifter and the mounts may beselectively coupled. In still other embodiments the mount comprises apedestal releasably coupled to the frame and a cradle adapted to receivethe cylindrical body.

Additional embodiments provide such assemblies where the frame has atleast two lateral beams joined by cross-members. The mount is releasablycoupled to the lateral beams and is adapted to slide along the beamswhen the shifter is actuated. In other embodiments a bearing element isdisposed between the mount and the frame.

In still other embodiments the assembly comprises a hydraulic cylindercoupled to the shifter.

In other aspects and embodiments, the invention provides methods ofbreaking down a flow line with a shifter mounted on a frame. The flowline comprises a plurality of components joined by unions along a commonaxis. The unions allow the components to be made up and broken down. Thecomponents are releasably coupled to the frame to restrict movementalong the axis and, when released, adapted to translate relative to theframe along the axis. The method comprises unjoining a first componentfrom a second component. The second component is uncoupled from theframe. The shifter is then actuated to move the second component on theframe along the axis away from the first component.

In still other aspects and embodiments, the invention provides methodsof making up a flow line with a shifter mounted on a frame. The flowline comprises a plurality of components joined by unions along a commonaxis. The unions allow the components to be made up and broken down. Thecomponents are releasably coupled to the frame to restrict movementalong the axis and, when released, adapted to translate relative to theframe along the axis. The method comprises placing a first component anda second component on the frame. The shifter is actuated to move thesecond component on the frame along the axis toward the first component.The first and second components then are joined.

Yet other aspects and embodiments of the invention provide assembliesfor manifolding the discharge from a plurality of pumps. The assembliescomprise a missile and a connection arm. The missile comprises a conduitadapted to receive flow from the pumps through feed inlets. Theconnection arm comprises a swivel joint. The connection arm is joined atone end to a feed inlet. Its other end is adapted to be joined to adischarge line from a pump by a union. The assemblies also comprise anadjustable support. The adjustable support engages a horizontal portionof the connection arm proximate to the feed inlet. The adjustablesupported is adapted for vertical adjustment.

Other embodiments provide such assemblies where the support comprises acradle, a base, and a vertically adjustable connector. The cradlesupports the horizontal portion of the connection arm. The verticallyadjustable connector extends between the cradle and the base and isadapted to raise or lower the cradle relative to the base. In otherembodiments the connector is a threaded shaft.

Other embodiments and aspects of the invention provide frac manifoldscomprising a frame. The frame supports a low-pressure suction lineadapted to supply fluid to a plurality of pumps, a missile adapted tomanifold the discharge from the plurality of pumps, a hydraulic systemcomprising a hydraulic actuator and an electrically powered hydraulicpump, an electric generator, and an internal combustion engine adaptedto power the electric generator. In other embodiments the engine is agasoline powered engine. In still other embodiments the hydraulicactuator drives jackup legs.

Other aspects and embodiments of the invention provide offset lateralcross junction fittings for flow lines. The junction fittings areadapted to manifold the discharge from a plurality of pumps and comprisea body having a primary bore and at least two feed bores. The primarybore extends axially through the body between first and second primaryunion faces. The union faces are adapted for connection to a flowlinecomponent by a flange union. The feed bores extend through the body froma feed union face to an intersection with the primary bore. The feedunion faces are adapted for connection to a component of a dischargeline from a the frac pump by a flange union. The intersection betweenthe feed bores and the primary bore has an interior angle ofsubstantially less than 90° and the intersections of the feed bores areoffset axially from each other.

Additional embodiments provide such fittings where the body iscylindrical, where the body is machined from a cylindrical bar, wherethe body is polyhedral.

In other aspects, the invention provides such junction fittings where atleast one feed bore forms a long-sweep curve into the primary bore,preferably where the feed bore has a sweep ratio of from about 1.25 toabout 8. Other embodiments provide such fittings where the feed boresintersect with the primary bore at an interior angle of about 45° or atan interior angle of from about 15° to about 60°.

Further embodiments provide such fittings which have a weep portextending from the primary faces or the feed faces to the exterior ofthe fitting.

Still other embodiments provide flow lines for a high-pressure fluidtransportation system. The flow lines comprise various embodiments ofthe novel flowline fittings. The flowline fittings are assembled intothe flow line by flange unions and connected to discharge lines from thepumps by flange unions. Other embodiments provide high-pressure fluidtransportation systems which comprise various embodiments of the novelflow lines. Additional embodiments provide skidded or trailered fracmanifolds comprising various embodiments of the novel flowline fittingsand at least one low-pressure line. Other embodiments provide methods ofassembling a flow line for a high-pressure fluid transportation system.Various embodiments of the novel flowline fittings are assembled intothe flow line by connecting them to a flowline component by a flangeunion.

Other aspects and embodiments of the invention provide feed fittingswith long-sweep curves. The feed fittings are adapted to combine theflow from at least two flowlines and comprise a body having astraight-line primary bore and a feed bore. The primary bore extendsaxially through the body between first and second primary union faces.The union faces are adapted for connection to a flowline component by aflange union. The feed bore extending through the body from a feed unionface to an intersection with the primary bore. The feed union face isadapted for connection to a flowline component by a flange union. Thefeed bore forms a long sweep curve into the primary bore.

Other embodiments provide such feed fittings where the feed bore has asweep ratio of from about 1.25 to about 8. Still other embodimentsprovide such fittings where the feed bore intersects with the primarybore at an angle of approximately 900, where the feed bore intersectswith the primary bore at an interior angle of about 45°, or where thefeed bore intersects with the primary bore at an interior angle of fromabout 15° to about 60°. Additional embodiments provide such feedfittings where the fitting comprises a second the feed bore.

Further embodiments provide such fittings which have a weep portextending from the primary faces or the feed faces to the exterior ofthe fitting.

Further aspects and embodiments provide flow lines for a high-pressurefluid transportation system which comprise various embodiments of thenovel feed fittings. Still other embodiments provide high-pressure fluidtransportation systems comprising various embodiments of the novel flowlines. Additional embodiments provide methods of assembling a flow linefor a high-pressure fluid transportation system. Various embodiments ofthe novel feed fittings are assembled into a flow line by connecting thefeed fitting to a flowline component by a flange union.

In other embodiments and aspects, the invention provides flowlinejunction fittings adapted to manifold the discharge from a plurality ofpumps. The junction fittings comprise a body having a primary bore andat least two feed bores. The primary bore extends axially through thebody. The feed bores extend through the body from a feed union face toan intersection with the primary bore. The feed union face is adaptedfor connection to a component of a discharge line from a frac pump by aflange union.

Other embodiments provide such fittings where the intersections of thefeed bores with the primary bore are offset axially from each otheralong the primary bore. In yet other embodiments the intersectionbetween the feed bores and the primary bore has an interior angle ofsubstantially less than 90°, and in still other embodiments, the feedbore forms a long sweep curve into the primary bore.

Additional embodiments provide such fittings where the body iscylindrical and where the body is machined from a cylindrical bar.

Still other embodiments and aspects of the invention provide methods ofinspecting a flow line in a fluid transportation system. The systeminjects fluid under high pressure into a well and incorporates a singleflow line running from the discharges from a plurality of pumps to awell head. The method comprises running an in-line inspection toolthrough the single flow line. In other embodiments the in-lineinspection tool is selected from the group consisting of cameras,magnetic-flux leakage units, magnetic particle detection units,electromagnetic acoustic transducers, pit gauges, calipers, and 3-Dlaser units.

In yet other embodiments, the inspection methods comprise flushing theflowline prior to running the in-line inspection tool through the singleflow line. In additional embodiments the flow line comprises a missilehaving a port in its upstream end allowing flush fluid to be introducedinto the missile.

Finally, still other aspects and embodiments of the invention provideapparatus and methods having various combinations of such features aswill be apparent to workers in the art.

Thus, the present invention in its various aspects and embodimentscomprises a combination of features and characteristics that aredirected to overcoming various shortcomings of the prior art. Thevarious features and characteristics described above, as well as otherfeatures and characteristics, will be readily apparent to those skilledin the art upon reading the following detailed description of thepreferred embodiments and by reference to the appended drawings.

Since the description and drawings that follow are directed toparticular embodiments, however, they shall not be understood aslimiting the scope of the invention. They are included to provide abetter understanding of the invention and the manner in which it may bepracticed. The subject invention encompasses other embodimentsconsistent with the claims set forth herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the U.S. Patent and TrademarkOffice upon request and payment of the necessary fee.

FIG. 1 (prior art) is a schematic view of a system for fracturing a welland receiving flowback from the well, which system includes varioushigh-pressure flow lines, such as flow lines 12 and 14.

FIG. 2 is a schematic view of a frac system incorporating a firstpreferred, trailer mounted embodiment 110 of the novel frac manifolds ofthe subject invention. Missile 113 of frac manifold 110 is coupled to asingle flow line 114 running to junction head 115 of zipper manifold 16,thus providing a single high-pressure conduit 100 between pumps 10 andzipper manifold 16.

FIG. 3 is a side elevation view of trailer-mounted frac manifold 110showing missile 113 of frac manifold 110 and a first preferredembodiment of the flowline components of the subject invention, namely,offset cross junction 120 having long sweep feed bores. FIG. 3A is anenlarged portion of FIG. 3.

FIG. 4 is a top view of frac trailer 110 shown in FIG. 3, an enlargedportion thereof being shown in FIG. 4A.

FIG. 5 is a front elevation view of a first preferred embodiment 170 ofthe novel adjustable feed arm supports, which adjustable support 170 isincorporated into frac trailer 110.

FIG. 6 is a side elevation view of adjustable support 170 shown in FIG.5.

FIG. 7 is a partial, enlarged isometric view, taken generally from aboveand to the right of frac trailer 110 shown in FIGS. 3-4 with certaincomponents removed to better show adjustable support 170 and a firstpreferred embodiment 150 of the novel assemblers.

FIG. 8 is another partial, enlarged isometric view, taken generally fromabove and to the right, of frac trailer 110.

FIG. 9 is another partial, enlarged isometric view, taken generally frombelow and to the right, of frac trailer 110.

FIG. 10 is an isometric view of novel flow line 100 comprising missile113 of frac trailer 110 and high-pressure flow line 114.

FIG. 11 is an elevation view of flow line 100 shown in FIG. 10.

FIG. 12 is an isometric view, with an axial quarter-section removed, ofoffset cross junction 120 which is assembled into missile 113 of fracmanifold 110 shown in FIGS. 3-9.

FIG. 13 is a cross-sectional view of offset cross junction 120 shown inFIG. 12.

FIG. 14 is an isometric view of offset cross junction 120 shown in FIGS.12-13 showing a flush-port assembly 190 assembled thereto.

FIG. 15 is a side elevation view of frac trailer 110 connected to afirst preferred embodiment 210 of the novel modular frac manifoldshaving four jackup legs 211.

FIG. 16 is a top view of frac trailer 110 connected to modular fracmanifold 210.

FIG. 17 is a side elevation view of modular frac manifold 210 shown inFIGS. 15-16.

FIG. 18 is a top view of modular frac manifold 210.

FIG. 19 is an isometric view of a portion of modular frac manifold 210,various components thereof having been removed to show jackup legs 211in greater detail.

FIG. 20A and FIG. 20B are isometric views of other preferred jackup legs311 which may be extended horizontally away from, for example, modularfrac manifold 210. FIG. 20A shows jackup legs 311 in a fully retractedposition. FIG. 20B shows jackup legs 311 in a fully extend position.

FIG. 21 is an isometric view of a second preferred embodiment of theflowline components of the subject invention, namely, an offset crossjunction 220 having straight-line feed bores which may be used, forexample, in missile 113 of frac trailer 110.

FIG. 22 is a cross-sectional view of offset cross junction 220 shown inFIG. 21.

FIG. 23 is an isometric view, with an axial quarter-section removed, ofa third preferred embodiment of the flowline components of the subjectinvention, namely, an offset lateral cross junction 320 havinglong-sweep feed bores which may be used, for example, in missile 113 offrac trailer 110.

FIG. 24 is a cross-sectional view of offset lateral cross junction 320shown in FIG. 23.

FIG. 25 is an isometric view of a fourth preferred embodiment of theflowline components of the subject invention, namely, an offset lateralcross junction 420 having straight-line feed bores which may be used,for example, in missile 113 of frac trailer 110.

FIG. 26 is a cross-sectional view of offset lateral cross junction 420shown in FIG. 25.

FIG. 27 is an isometric view of a fifth preferred embodiment of theflowline components of the subject invention, namely, a cross junction520 having right-angle feed bores which may be used, for example, inmissile 113 of frac trailer 110.

FIG. 28 is a cross-sectional view of right-angle cross junction 520shown in FIG. 27.

FIG. 29 is an isometric view of a cross junction 20 used in flow line114.

FIG. 30 is a cross-sectional view of cross junction 20 shown in FIG. 29.

FIG. 31 is an isometric view of a sixth preferred embodiment of theflowline components of the subject invention, namely, a tee junction 620having a long-sweep feed bore which may be used, for example, in flowline 114.

FIG. 32 is a cross-sectional view of tee junction 620 shown in FIG. 31.

FIG. 33 is an isometric view, with an axial quarter-section removed, ofa seventh preferred embodiment of the flowline components of the subjectinvention, namely, a lateral junction 720 having a long-sweep feed borewhich may be used, for example, in flow line 114.

FIG. 34 is a cross-sectional view of lateral junction 720 shown in FIG.33.

In the drawings and description that follows, like parts are identifiedby the same reference numerals. It also will be apparent from thediscussion that follows that certain conventions have been adopted tofacilitate the description of the novel systems which typically includelarge numbers of identical components. For example, as discussed below,various embodiments of the novel missiles include a plurality ofidentical cross junctions 120. Specific individual cross junctions 120may be identified in the drawings, or referenced in the discussion as120 a, 120 b, 120 c, etc. to distinguish a particular junction 120 fromanother junction 120. The drawing figures also are not necessarily toscale. Certain features of the embodiments may be shown exaggerated inscale or in somewhat schematic form and some details of conventionaldesign and construction may not be shown in the interest of clarity andconciseness. For example, in large part the threaded fasteners used tojoin flange unions are omitted.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The invention, in various aspects and embodiments, is directed generallyto fluid transportation systems and flow lines used in those systems,and especially to frac trailers, frac manifolds, flow lines, andflowline components that are used to convey abrasive, corrosive fluidsunder high pressure. Various specific embodiments will be describedbelow. For the sake of conciseness, however, all features of an actualimplementation may not be described or illustrated. In developing anyactual implementation, as in any engineering or design project, numerousimplementation-specific decisions must be made to achieve a developer'sspecific goals. Decisions usually will be made consistent withinsystem-related and business-related constraints. Specific goals may varyfrom one implementation to another. Development efforts might be complexand time consuming and may involve many aspects of design, fabrication,and manufacture. Nevertheless, it should be appreciated that suchdevelopment projects would be routine effort for those of ordinary skillhaving the benefit of this disclosure.

The novel frac manifolds, flowlines, and flowline components typicallywill be used to connect process or flow units for temporary fluidtransportation systems. They are particularly useful for temporaryinstallations that must be assembled and disassembled on site and whichmay be installed at various sites. Such systems are common in chemicaland other industrial plants, on marine dredging vessels, strip mines,and especially in the oil and gas industry. Frac systems, such as thoseshown in FIG. 1, are a very common application where temporaryhigh-pressure flow lines are routinely assembled and disassembled atvarious sites to provide fluid conduits between process or flow unitsfor different wells.

The novel frac manifolds, flow lines, and flowline components areparticularly suited for use in frac systems such as the system shown inFIG. 1. For example, a first preferred embodiment 110 of the fracmanifolds of the subject invention is shown schematically in FIG. 2.Frac manifold 110, and the novel frac system shown in FIG. 2, isidentical in many respects to frac manifold 9 and the frac system ofFIG. 1. It will be noted that frac manifold 9 incorporates a pair ofrelatively small diameter missiles 13, one on each side of frac manifold9. The two missiles 13 receive the discharge from pumps 10, aremanifolded, and discharge into four relatively small diameterhigh-pressure flow lines 14 which feed into goat head 15.

In contrast, novel frac manifold 110 incorporates a single missile 113to which are connected all of the pump discharge lines 12. Missile 113receives the entire discharge of pumps 10. Single missile 113 in turndischarges into a single flow line 114 running to junction head 115 ofzipper manifold 16. Flow line 100, i.e., the assembly of missile 113 andflow line 114, thus provides a single high-pressure conduit betweenpumps 10 and zipper manifold 16.

Frac manifold 110 is shown in further detail in FIGS. 3-4. As seentherein, frac manifold 110 is a trailer mounted manifold. It generallycomprises a rolling chassis 130, missile 113, a number of missile mounts140, an assembler 150 for making up and breaking down missile 113, anumber of connection arms 160, adjustable mounts 170, and a suctionsystem 180. Suction system 180 receives slurry from blender 6 viablender hoses 7 (not shown in FIGS. 3-4) and distributes it to pumps 10.As noted above, missile 113 receives the high-pressure discharge frompumps 10, manifolds it, and discharges it into flow line 114.

Chassis 130 provides the primary structural framework for frac trailer110. It is the frame on which missile 113, suction system 180, and theother trailer components are mounted, either directly or indirectly. Itincludes a pair of lateral beams, such as shaped I-beams 131. I-beams131 are connected by cross members 132. Structural steel having otherconfigurations, such as C-beams, may be used as well. Chassis 130 is arolling chassis, and thus includes a suspension system, a wheelassembly, and a hitch assembly. Trailer 110 also preferably is providedwith a mechanism for lifting the forward end of chassis 130, such ashydraulic jacks 111. Jacks 111 enable trailer 110 to be more easilyhitched to, and unhitched from a tractor as required. It also will benoted that chassis 130 is configured such that when trailer 110 isunhitched, it will rest on the ground. In particular, I-beams 131 willrest on the ground, providing an extensive, stable foot print fortrailer 110 when it is in service.

Suction system 180 generally comprises a suction manifold 181 and a pairof suction lines 182. Suction manifold 181 is mounted near the rear oftrailer 110. It has a transverse main pipe from which extend two lateralpipes, one on each side of trailer 110. The main pipe of suctionmanifold 181 is provided with a number of connections, such as femalehammer union subs 183, allowing suction manifold 181 to receive andmanifold the discharge from blender 6 via blender hoses 7 (not shown inFIGS. 3-4). Suction lines 182 are connected to the lateral pipes ofsuction manifold 181 by, for example, flange unions. Suction lines 182may be mounted on chassis 130 along each side of trailer 110 by suitablemounts, and may be mounted permanently, for example, by welds.Preferably, however, they are mounted to allow disassembly from trailer110. For example, suction lines 182 are mounted on brackets 184 whichare spaced along and extend from the side of I-beams 131. Brackets 184include a cradle and a removeable top clamp or strap. Suction lines 182thus may be securely held on brackets 184, but may be easily assembledto and disassembled from trailer 110.

Each suction line 182 includes a plurality of outlets. For example,suction lines 182 each have six outlets which are provided withconnections, such as female hammer union subs 185. Suction hoses 11leading to pumps 10 (not shown in FIGS. 3-4) may be connected via hammerunions to hammer union subs 185. Pumps 10 on one side of frac trailer110 may be connected to one suction line 182, and pumps 10 on the otherside may be connected to the other suction line 182. It will beappreciated, of course, that other conventional unions and conduits maybe used to make up the connections with blender 6 and pumps 10.

Missile 113 incorporates a first preferred embodiment of the novelflowline components, offset cross junction 120. More specifically,missile 113 has six offset cross junctions 120 a-120 f which areinterconnected by spools 30 a-30 e. Offset cross junctions 120 a-120 f,as discussed further below, are connected to an array of pumps 10 viapump discharge lines 12 (not shown in FIGS. 3-4) and connection arms160. More specifically, each offset cross junction 120 a-120 f isconnected to two pumps 10 positioned on opposite sides of frac trailer110. They may be referred to as “cross” junctions in that, as describedbelow, they have two feed bores entering a primary conduit. They may bereferred to as an “offset” cross junction in that the feed bores areoffset axially from each other along the primary conduit.

Offset cross junctions 120 are shown in greater detail in FIGS. 12-13.As seen therein, offset cross junctions 120 have a somewhat elongated,generally cylindrical body 121 having a main or primary bore 122. Bore122 provides the primary conduit through which slurry passes as it isconveyed towards well head 17. Primary bore 122 extends betweenopposing, generally parallel, flat surfaces or union faces 123 on eachend of body 121. Union faces 123 may be viewed as the primary unionfaces for junctions 120. The center of bore 122 may be viewed asdefining the central axis of offset cross junction 120.

As appreciated from FIG. 12, union faces 123 are provided with, forexample, 16 bottomed holes 124. Holes 124 typically are threaded toaccept standing bolts or other threaded connectors (not shown).Alternately, holes 124 may be adapted to receive threaded studs (notshown). Holes 124 are arranged angularly about bore 122. When providedwith studs or other threaded connectors, mating components, such asspools 30 may be joined to offset cross junctions 120 by a flange-typeunion. More or fewer holes 124 and connectors may be provided dependingupon the size of the union between the components and the pressures forwhich the union will be rated.

Typically, union faces 123 will be provided with a metal seal (notshown). The seal is disposed in a groove, such as annular groove 125extending around the openings of bore 122. A seal is generally requiredto avoid leakage at union faces 123. If desired, weep ports, such asweep port 125′, may be provided in cross junctions 120. As seen best inFIG. 12, weep ports 125′ are relatively small passageways extendingangularly through body 121 of cross junction 120. They extend from sealgrooves 125 in union faces 123 to the outer surface of cross junction120. If there is any leakage around the metal seal and union faces 123,it may be more easily detected by monitoring weep port 125′ for anydischarge of fluid. Weep port 125′ may have other configurations, suchas intersecting bores. In any event, weep ports 125′ may allow arelatively minor leak to be addressed before developing into a moreserious situation.

Also, and though described as “flat” herein, union faces 123 typicallywill have a very slight annular boss extending upwards around theopenings of bore 122. The annular boss will help ensure that theabutment between mating union faces is properly loaded when the union ismade up. The designs and features of union faces in particular andflange unions in general are well known, however, and the union faces onjunction 120 and the other fittings disclosed herein may be varied inaccordance with common practice in the art.

Offset cross junctions 120 also are provided with a pair of bores 126which provide conduits for feeding discharge from an individual pump 10into primary bore 122. Feed bores 126 extend inward from flat unionfaces 127 which are milled or otherwise provided on the outer surface ofbody 121. Feed union faces 127 are on opposite sides of body 121, i.e.,they are spaced 180° about the circumference of body 121, and aregenerally parallel.

Feed bores 126 lead into and intersect with primary bore 122. It will benoted that bores 126 form what may be referred to as long-sweep curvesleading into primary bore 122. As used herein, a “long-sweep” curve,when used in reference to a particular bore or passage, shall beunderstood as meaning that the sweep ratio of the bore is about 1.25 orgreater. The “sweep ratio” in turn shall be understood as the ratio ofthe radius of the curve to the diameter of the bore in which the curveis formed. The sweep ratio of bores 126 is approximately 2.5.

It also will be noted that feed bores 126 are offset axially from eachother. That is, their respective intersections with primary bore 122 arespaced apart along the length or axis of primary bore 122. Thus, feedbores 126 will discharge into primary bore at spaced intersections, oneupstream from the other. As discussed further below, providing along-sweep in feed bores 126, and offsetting the intersections betweenfeed bores 126 and primary bore 122 will help to minimize areas ofconcentrated erosion in cross junctions 120.

Like primary union faces 123, feed union faces 127 comprise a pluralityof holes 128, in this case 8. Mating components may be joined to offsetcross junctions 120 by threaded studs or other threaded connectorsinserted in holes 128. Feed union faces 127 also will have a metal seal(not shown) disposed in an annular groove 129. Weep ports, similar toweep ports 125′, also may be provided between seal grooves 129 and theouter surface of cross junction 120. Like union faces 123, feed unionfaces 127 may be varied in accordance with common practice in the art.

Offset cross junctions 120 a-120 f are joined by spools 30 a-30 e.Spools 30 are conventional spools. As such they comprise a pipe whichprovides a conduit for conveying fluid between offset cross junctions120. A pair of flanges are provided at each end of the pipe. The outerflat surfaces of the flanges provide union faces. Each of the flanges isprovided with, for example, 16 bolt holes extending through the flanges.The holes are adapted to accommodate the passage of threaded connectors,such as threaded studs or bolts. The holes allow spools 30 to be joined,for example, to cross junctions 120 in missile 113. The flanges alsopreferably are provided with a metal seal. The union faces on spools 30,however, may be varied as desired in accordance with common practice inthe art.

As described in further detail below, cross junction 120 f of missile113 will be connected via a flange union to other flowline components. Ablind flange may be used to close off cross junction 120 f while fractrailer 110 is being stored or transported. Cross junction 120 a, whichis disposed toward the end of frac trailer 110 and is the most upstreamcross junction 120, also may be provided with a blind flange closing offthe upstream end of missile 113 during storage and transportation.Preferably, however, cross junction 120 a is provided with a port thatwill allow missile 113 to be flushed and cleaned out between operations.

For example, as seen best in FIG. 14, a flush-port assembly 190 isassembled to cross junction 120 a. Flush-port assembly 190 generallycomprises a ported flange 191 and a flanged female hammer union sub 192.Flange 191 has a port (not visible). The port extends through flange 191to an outer union face (not visible). Thus, flange 191 is joined tocross junction 120 a, and flanged female hammer union sub 192 is joinedto port flange 191 by flange unions. A flush line, therefore, may beconnected to female sub 193 by a hammer union to pump fluid throughmissile 113 to flush out fluids and particulates from prior operations.Otherwise, the port in assembly 190 may be shut off by a blind malehammer union sub joined to female sub 193. It will be appreciated, ofcourse, that a flanged flush line may be connected directly to portedflange 191. Likewise, other types of flange union subs may be joined toported flange 191, or that other types of union subs may be formedintegrally with ported flange 191.

Thus, in contrast to conventional frac manifold 9, which has tworelatively small manifolding missiles 13 which themselves aremanifolded, novel frac trailer 110 comprises a single, larger, straightmissile 113 which receives the discharge from all pumps 10. That is, inconventional frac systems, such as those shown in FIG. 1, pumps 10 willbe lined up on both sides of frac manifold 9. Pumps 10 on one side offrac manifold 9, as represented schematically in FIG. 1, typically willfeed into the missile 13 running along that side of frac manifold 9.Pumps 10 which are lined up on the other side will feed into the missile13 running on the other side of frac manifold 9. Missiles 13 aremanifolded by a section of pipe which connects their downstream ends atright angles. The combined discharge from missiles 13 then isdistributed into four high-pressure flow lines 14 which run to goat head15.

As shown schematically in FIG. 2, pumps 10 from both sides of fracmanifold 110 all feed into missile 113. Each offset cross junction 120allows two pumps 10 to feed into missile 113 from opposite sides oftrailer 110. Frac trailer 110, therefore, will have a simpler, lesscluttered design. It may be assembled more easily, and when in service,will allow greater access to manifold components for hook up andservice. More importantly, however, novel frac manifolds incorporating asingle, larger missile, such as missile 113, should provide better wearresistance and a longer service life than conventional frac manifoldsincorporating multiple missiles.

That is, the slurry flowing through flow lines is highly abrasive andcorrosive, moves at relatively high velocities under high pressure, andis quite turbulent in many areas. Consequently, flowline components tendto suffer material loss which can weaken the part and shorten itsservice life. The material loss results from a number of differentdynamics, including ductile erosion and brittle erosion, both of whichare exacerbated by corrosion.

Ductile erosion results from entrained sand and other particles draggingalong the inner walls and cutting or ploughing into the walls. The angleof impingement typically is small, less than 30°. Ductile erosion is theprimary dynamic in relatively straight sections of flow lines. Brittleerosion results from entrained sand impinging on the walls at or nearnormal to the surface, the impact causing tiny radial cracks in thewall. Brittle erosion is the primary dynamic in turbulent areas of theflow line, or where the flow line changes direction.

It also will be appreciated that corrosion generally tends to weakenmaterial in the part. The part, therefore, is more susceptible to bothductile and brittle erosion. Moreover, since flowline componentstypically are manufactured from relatively hard steels, brittle erosionfrom near normal impacts caused by more turbulent flow typically plays alarger role than ductile erosion resulting from more laminar flow.

For example, turbulence and brittle erosion is the primary dynamic inthe area where pump discharge lines 12 feed into missiles 13 ofconventional frac manifold 9. Fluid from discharge lines 12 immediatelyhits the other side of missile 13, which is only a few inches away. Morespecifically, the inner diameter of high-pressure missiles inconventional frac manifolds typically will be sized such that theycumulatively provide the required flow rates (up to 100 bbl/minute)without excessively high fluid velocity through the missiles. The upperlimit, often referred to as the erosional fluid velocity, generally isabout 40 ft/sec. Thus, missiles in conventional frac manifolds typicallywill be made up from 3″ or 4″ components having, respectively, innerdiameters of 2.75″ and 3.5″.

In contrast, novel flow lines having comparable flow rates andvelocities preferably will have conduits have a diameter of at leastabout 5 inches or, more preferably, at least about 7 inches. Forexample, cross junctions 120 may have a primary bore of about 5 inchesor 7 inches. Spools 30 preferably have similar dimensions. Thus, it willbe appreciated that fluid entering primary bore 122 of offset crossjunctions 120 from feed bores 126 will have more room to spread inmissile 113. The quantity and velocity of particles impinging on theother side of primary bore 122 at near normal angles will be less thanexperienced by smaller diameter pipes, such as missiles 13 inconventional frac manifold 9.

In addition, by providing feed bores 127 with a long-sweep curve insteadof a straight-line bore, fluid discharged from feed bores 127 will bedirected at an angle more along, and less across the flow of fluidthrough primary bore 122. Thus, the average angle of impact forparticles flowing into primary bore 122 will be diminished. To a certainextent the reduction of average impact angle on the other side ofprimary bore 122 will come at the expense of feed bore 122. Impacterosion will be greater in feed bore 126 than if it were a straightbore. By providing a long-sweep curve, however, the increase in impacterosion in feed bores 126 will be minimized.

Moreover, offsetting the junctions between feed bores 126 and primarybore 122 will help to minimize areas of concentrated turbulence anderosion in cross junctions 120. Turbulence created by fluid enteringprimary bore 122 from an upstream feed bore 126 will tend to diminish,and the flow will become more laminar as fluid travels down primary bore122. Feed bores 126, therefore, preferably are spaced at sufficientdistances to allow turbulence from one feed bore 126 to substantiallysubside before the discharge from the downstream feed bore 126 entersprimary bore 122. For example, feed bores 126 may be offset a distanceat least approximately equal to the diameter of feed bores 126, and morepreferably, at a multiple thereof. Feed bores 126 as illustrated inFIGS. 12-13, for example, are offset by a factor of approximately 7relative to their diameters. Providing a long-sweep curve in feed bores126 also will create less initial turbulence, and therefore, laminarflow through cross junction 120 will recover more quickly.

It also will be noted that offset cross junctions 120 may be providedwith significantly thicker walls than are present in traditionalfittings. More specifically, cross junctions 120 and other embodimentsof the novel junction fittings preferably are provided with relativelythick walls as compared to junction fittings used in conventional fracmanifolds. The ratio of the minimum width of their body to the diameterof their primary bore preferably is at least about 3:2, and morepreferably at least about 2:1 or 3:1. Alternately stated, the minimumthickness of the wall surrounding the primary bore is preferably atleast about 25%, and more preferably at least about 50% or 100% of thediameter of the primary bore. For example, body 121 of cross junction120 is generally cylindrical with a centrally disposed primary bore 122.Its minimum width is equal to the outer diameter of body 121. Asillustrated, the outer diameter of body 121 is about 3 times as great asthe diameter of primary bore 122, and the walls of primary bore 122 areapproximately as thick as its diameter.

Junctions 120 also preferably are manufactured by starting with agenerally cylindrical bar, machining primary bore 122, heat treating,and then machining the remaining features, such as feed bores 126,annular grooves 125 and 129, and the annular boss. It will beappreciated that at such thickness, it is difficult or impossible tobend tubular stock. Thus, despite its relatively thick walls, feed bores126 may be provided with long sweep curves, and at the same timejunction 120 can tolerate more erosion before reaching a point where theintegrity of the fitting is compromised.

Frac manifolds also are usually mounted on a skid or trailer so thatthey may be transported easily to and from a well site. That is asignificant advantage. The need to transport the manifold over roads andhighways without special permits, however, limits the size of the skidor trailer and can create significant spatial constraints in the designand layout of the manifold. Frac manifolds having two or more missiles,such as frac manifold 9, require very sharp turns in the high-pressureflow lines and often more junctions. For example, each missile typicallywill make a right turn, or it will tee into a manifolding pipe. Suchturns and junctions are particularly susceptible to erosion. They may beeliminated in the novel frac manifolds, such as frac trailer 110, whichhas a single, straight missile, such as missile 113, accepting dischargefrom pumps 10 on both sides of missile 113.

Perhaps most importantly, it has been observed that the discharge offluid from the array of pumps creates significantly less vibration invarious embodiments of the novel missiles. Conventional frac manifoldsexperience substantial vibration as fluid is pumped through the missilesand the rest of the system. The vibration is visibly noticeable inconventional systems, but not so in embodiments of the novel missiles.Surprisingly, vibration through the entire high-pressure side of asystem, for example, in flow lines running from the manifold to the wellhead or zipper manifold, is reduced significantly as well. It isbelieved that by offsetting the flow into novel missiles, particularlywith larger inner primary bores, significantly less vibration iscreated. Flow into conventional frac missiles typically impinges atright angles against a relatively smaller conduit.

Discharge lines 12 of pumps 10 ultimately are connected to offset crossjunctions 120 of missile 113 through a flange union with a flangedcomponent. Discharge lines 12, for example, may terminate in a flangedsub allowing them to be connected directly to cross junctions 120 atfeed union faces 127. Discharge lines 12 of pumps 10 then may beconnected to cross junctions 120 by flange unions. Discharge lines 12may terminate in a hammer union sub, and cross junctions 120 providedwith a flanged, mating hammer union sub. Preferably, however, pumpdischarge lines 12 are connected to missile 113 by connection arms 160shown in FIGS. 3-4 and 7-9.

Connection arms 160 comprise a flanged, female sub 161 of a hammer unionwhich is joined to cross junctions 120 at feed union face 127 by aflange union. A swivel joint 162 is connected to female sub 161 via ahammer union 163. The other end of swivel joint 162 is connected to astraight pipe section 164, also via a hammer union. Straight pipe 164terminates in a female hammer union sub, allowing it to be connected todischarge lines 12 of pumps 10 via a hammer union. It will beappreciated, however, that other types of connections may be providedand that connection arms 160 may have various conventional designs.Likewise, cross junctions 120 may be provide with other integralfeatures, such as a hammer union sub formed therein, to allow dischargelines to be connected in other ways.

In any event, connection arms 160 facilitate connection to pumps 10 byswinging out and away from missile 113 and frac trailer 110. The end ofstraight pipe 164 may be situated so that connections to pump dischargelines 12 may be made up more easily and safely. Preferably, suitablerests, such as cradle rests 165, are provided to support the end of pipe164 and relieve stress on swivel joint 162 when trailer 110 is not inuse. Cradle rests 165 also preferably include retainers to secure theend of pipe 164 when trailer 110 is being moved.

It will be appreciated that connection arms 160 are heavy. Whenextended, they can create significant stress on their connections tocross junctions 120, especially hammer union 163. Thus, frac trailer 110may be provided with conventional supports which provide verticalsupport for connection arms 160 near where they are joined to missile113. Such conventional supports can relieve stress on connections suchas hammer unions 163, but must be precisely sized and assembled toproperly align with the connection. If too short, they may notsufficiently relieve stress caused by the weight of connection arms 160.If too tall, they may create stress in hammer unions 163.

Thus, and in accordance with other aspects of the invention, connectionarms 160 are supported by adjustable supports, such as adjustablesupports 170 seen best in FIGS. 5-9. Supports 170 comprise a rest, suchas split collar 171. Split collar 171 has a pair of mating,semi-cylindrical or u-shaped halves 171 a and 171 b that fit around theend of swivel joint 162 of connection arms 160 near hammer union 163.Each collar half 171 a and 171 b has ears allowing them to be connectedby nuts and bolts or other fasteners. The end of swivel joint 162,therefore, may be secured within collar 171. If desired, elastomergaskets may be provided between swivel joint 162 and collar 171.

Collar 171 is supported by a stand 172 mounted on a base 173. Base 173is mounted on trailer 110, preferably releasably so. For example, base173 generally is a plate-like component, one end of which is formed intoa curve allowing it to rest on one of the suction lines 182. The otherend of base 173 has a slot allowing it to be releasably connected to oneof the lateral beams 131, for example, by a nut and bolt. Stand 172comprises a plurality of mating buttresses 174 and a generallycylindrical, vertical passage 175 in the upper portion thereof. (Passage175 is hidden in the figures, but its general location is identified inFIGS. 5-6.) A threaded adjuster 176 is fixedly connected at one end tocollar 171. The other end of threaded adjuster 176 extends into verticalpassage 175 in stand 172. Adjusting nuts 177 are provided on threadedadjuster 176.

Threaded adjuster 176, therefore, may be moved up or down by rotatingnut 177 in one direction or the other. Thus, stress on hammer union 163joining connection arm 160 to cross junction 120 may be more effectivelyminimized by the novel supports 170. Supports 170 may be adjustedvertically to allow collar 171 to be more accurately positioned relativeto hammer union 163.

Missile 113 preferably is mounted along the center of frac trailer 110on suitable mounts, for example, missile mounts 140. Missile mounts 140in turn are mounted on trailer chassis 130. More specifically, eachoffset cross junction 120 of missile 113 is supported by a missile mount140. Missile mount 140 in turn generally comprises a cradle 141 and apedestal 142.

Cradles 141 may be viewed as lateral segments of an open cylinder, andthus provide a curved surface upon which offset cross junctions 120 mayrest. Preferably, junctions 120 fit relatively closely therein and arereleasably secured to cradles 141. For example, threaded studs may beanchored in junction 120 and extend through suitable openings in cradle141, allowing junction 120 to be secured within cradle 141 by threadednuts. Other threaded connectors, and other connectors, however, may beused.

Preferably, as seen best in FIGS. 3A, 4A, and 7-8, cradle 141 will bedimensioned such that it extends over a substantial portion of thebottom half of junction 120. In particular, the inner, transverse arc ofcradle 141 preferably approaches 180°, and its length approaches that ofjunction 120 to enhance the lateral stability of junction 120 withincradle 141. Preferably, the arc of cradle 141 is at least about 150° andits length is at least about 50%, more preferably at least about 80% ofthe length of junction 120. Preferably, as shown, the length of cradle160 is such that it extends laterally beyond both feed union faces 127of junction 120. Thus, it will be appreciated that the connectionbetween junction 120 and cradle 141 is quite secure and rigid.

Pedestals 142 comprise a pair of standards 143 and a base 144. Standards143 extend vertically upward at each end of base 144 to the bottom ofcradle 141, supporting cradle 141 above chassis 130. Base 144 comprisesa symmetrical pair of spaced, horizontal plates. Each plate of base 144has a relatively short, vertical plate 145 running laterally along itsinner edge. Standards 143 straddle the plates of base 144 and have acutout. The cutout corresponds generally to vertical plates 145 and thegap between the base plates, thus creating a channel 146 runninglaterally through the lower part of mount 140. It also will be notedthat pedestals 142 extend over both I-beams 131 of chassis 130. Inparticular, both the bottoms of standard 143 and base 144 extend atleast partially over both I-beams 131. The tops of standards 143 alsoextend substantially around the bottom of cradle 141.

Standards 143, therefore, allow missile 113 to be tied structurally notonly to support members spanning I-beams 131, such as base 144, but alsodirectly to I-beams 131. That is, force generated by and within crossjunctions 120 will be transmitted across the width of base 144. Suchforces also will be transmitted to points directly above I-beams 131.Mounts 140, therefore, will be extremely resistant to both vertical andtransverse vibrational forces.

Mounts 140 may be more or less permanently incorporated into chassis130, for example, by welds. Preferably, however, mounts 140 arereleasably secured to chassis 130. For example, pedestals 142 aremounted to lateral I-beams 131 by bolts that extend through openings inpedestal base 144 and I-beam 131. The openings in base 144 preferablyare obround or otherwise somewhat laterally elongated to allow for someimprecision in mounting pedestals 142.

As noted, conventional frac manifolds experience considerable vibrationduring operation which is largely absent in embodiments of the novelmanifolds. While offsetting the flow into, for example, missile 113 andproviding it with a relatively large primary bore is believed tominimize the creation of vibrational forces, it also is believed thatthe assembly, location, and mounting of missile 113 on frac trailer 110aids in minimizing vibration. For example, the components of missile 113are joined by flange unions, creating a relatively rigid flow line.Hammer and clamp unions allow significantly more bending at the union,especially as the diameter of the components diminishes.

Missile 113 in frac trailer 110 also is centered between twointerconnected lateral frame members, namely I-beams 131 in chassis 130.Conventional frac manifolds may have a pair of lateral frame members,but they typically have a pair of missiles, each one mounted close to oreven outside of the lateral frame members. Although somewhat elevatedabove I-beams 131, missile 113 also is firmly connected to both I-beams131 by mounts 140. Mounts 140 provide extensive rigid connectingstructure between missile 113 and I-beams 131. I-beams 131 in turnprovide a relatively large, stable footprint for frac trailer 110.Surprisingly, vibration through the entire high-pressure side of thesystem, for example, in the flow line running from the manifold to thewell head or zipper manifold, is significantly reduced as well.

Flowline components are quite heavy and difficult to manipulate. Thus,the novel frac manifolds preferably incorporate systems to assist inmaking up, and breaking down the components. For example, assembler 150may be operated to help make up and break down cross junctions 120 andspools 30 in missile 113. As seen best in FIGS. 3 and 3A, assembler 150comprises a shifter 151, and a linear actuator 152.

Shifter 151 is an elongated shaft or rod-like member. It has a generallyopen, rectangular cross-section, but other configurations may beprovided. Shifter 151 extends laterally, more or less the length ofmissile 113 along the center line of chassis 130. It is mounted on topof frame cross members 132 and through channels 146 in mounts 140. Oneend of shifter 151 extends to a position under cross junction 120 atoward the rear of trailer 110. The other end of shifter 151 extendsunder cross junction 120 e near the front of trailer 110, where it isconnected to linear actuator 152. Linear actuator 152 is a hydrauliccylinder, but other linear actuators such as pneumatic cylinders orelectromagnetic actuators may be used. In any event, hydraulic cylinder152 will drive shifter 151 laterally back and forth. Bearing elements,such as hard elastomer pads 158, may be placed on frame cross members132 to facilitate movement of shifter 151.

Shifter 151 may be selectively and releasably coupled to any of crossjunctions 120 a to 120 e. For example, shifter 151 is provided withpairs of transversely opposed openings (not visible in figures) spacedalong its length. When missile 113 is made up, the shifter openingsalign with transversely opposed openings 147 provided through verticalplates 145 in base 144 of mounts 140. Shifter 151 may be releasablycoupled to a particular cross junction 120 by inserting a pin 156through openings 147 in its corresponding mount 140 and the openings inshifter 151. Openings 147 in mounts 140 may be obround or otherwiseelongated to allow for some imprecision in aligning them with theopenings in shifter 151. Other mechanisms for releasably connectingshifter 151 and mounts 140, however, are known and may be used ifdesired.

By selectively coupling and actuating shifter 151, the unions betweencross junctions 120 and spools 30 may be more easily made up and brokendown. For example, should the need arise, assembler 150 may be used todisassemble and replace a particular cross junction 120 from missile113, such as junction 120 c. Pin 156 may be placed through openings 147in mount 140 holding junction 120 c and the corresponding opening inshifter 151. Shifter 151 will thus be coupled to junction 120 c throughits mount 140. The bolts securing mounts 140 for cross junctions 120 a,120 b, and 120 c then will be removed, as will the nuts securing theunion between cross junction 120 c and spool 30 c. Mounts 140 forjunctions 120 d, 120 e, and 120 f will remain securely fastened tochassis 130.

Hydraulic cylinder 152 then may be actuated to move shifter 151 towardthe rear of trailer 110. Uncoupled mounts 140 will be able to slideacross frame I-beams 131. Thus, the entire subassembly of junction 120c, spool 30 b, junction 120 b, spool 30 a, and junction 120 a, alongwith the corresponding mounts 140, will be shifted rearward by shifter151, creating a gap between junction 120 c and spool 30 c. Bearingelements, such as hard elastomer pads 148, may be provided under base144 of mounts 140 to facilitate shifting of mounts 140.

The nuts securing the union between cross junction 120 c and spool 30 bthen may be removed. Cross junction 120 c will remain uncoupled fromchassis 130 and coupled to shifter 151. Hydraulic cylinder 152 then maybe actuated to move shifter 151 partially back toward the front oftrailer 110, to a point where junction 120 c is clear of both spool 30 band 30 c. Cross junction 120 c then may be removed, typically with theaid of a mechanical lift. A replacement junction 120 c may be assembledinto missile 113 by reversing the process described above.

Assembler 150 also may be used to make up or break down a connectionbetween missile 113 and flow line 114. Mounts 140 for all crossjunctions 120 will be uncoupled from chassis 130. Shifter 151 may becoupled to any of mounts 140. When actuated, hydraulic cylinder willdrive the entire missile 113 back and forth across chassis 130.

It will be appreciated that assembler 150 may be modified in variousways to accommodate different missile mounts. Similarly, instead ofproviding a selective, releasable connection between a shifter andmissile mounts, the shifter and mounts may be fixedly connected, andselective, releasable connections provided between the mounts and themissile. In such embodiments, the missile components would shift withinand along the stationary mounts. If a missile is mounted directly to aframe, a selective, releasable connection may be provided between ashifter and the missile components. Other modifications will be apparentto workers in the art.

The novel assemblers will allow the novel missiles to be made up andbroken down more easily and safely. Their application, however, is notlimited to the novel missiles or even to missiles in general. Variousother flow lines and flowline subassemblies, such as zipper manifolds,are commonly mounted on skids or other chassis. Components of flow line114, as another example, may be mounted on a skid provided with anassembler. The novel assemblers may be used to assist in making up andbreaking down the components of such units.

Trailer 110 may, and typically will incorporate other features commonlyprovided in conventional frac trailers, and the trailers themselves maybe of many different conventional designs. Chassis 130 can have otherconfigurations, and may incorporate any number of conventionalsuspension systems and wheel assemblies. Missile 113 and suction lines182 will be substantially horizontal when I-beams 131 are resting on asite pad, but hydraulic or other leveling mechanisms may be provided ifdesired. Hydraulic jacks 111, for example, may be used to level chassis130. Running and signal lights may be provided as desired or required byregulation. The hydraulic systems, such as hydraulic cylinder 152 inassembler 150 and jacks 111 may be actuated and controlled byconventional systems. Such systems typically will include hydraulicpumps, accumulators, lines, and valves, and digital controllers andoperation panels. Given that such features are well known to workers inthe art, they have largely been omitted from the figures for the sake ofclarity.

Preferably, however, trailer 110 is provided with a gasoline poweredinternal combustion engine, such as motor 133. Motor 133 may be used asa source of mechanical power allowing trailer 110 to be fullyoperational on site without the need for electrical hookups or otherexternal power sources. Toward that end, motor 133 will be used to drivea conventional electric generator. The generator, in turn, will be usedto power hydraulic systems on trailer 110, for example, the hydraulicpumps and valves associated with hydraulic cylinder 152 in assembler150. The electric generator also may be used to power the controlsystems for hydraulic systems or other electromechanical systems on thenovel trailers.

As discussed above, frac manifold 110 is a trailer mounted manifoldwhere missile 113, suction lines 182, and the other manifold componentsare mounted on rolling chassis 130. If desired, however, the novel fracmanifolds may be carried on the chassis of a truck, or they may becarried on a non-rolling chassis. In accordance with other broadembodiments of the invention, the novel missiles and other manifoldcomponents also may be mounted on a rolling or non-rolling chassis toprovide modular manifolds. Modular manifolds can provide greaterflexibility in meeting the requirements of particular fracturingoperations, which may call for greater or lesser numbers of pumps.

For example, as shown in FIGS. 15-16, frac trailer 110 is assembled to afrac manifold module 210. Modular manifold 210 in most respects isidentical to frac trailer 110. It comprises missile 113, missile mounts140, assembler 150, connection arms 160, and adjustable supports 170.The hydraulic system (not shown) actuating hydraulic cylinder 152 ofassembler 150 on modular manifold 210 may be driven by electrical powergenerated by frac trailer 110. Alternately, it may be connected toanother external source of electrical power, or modular manifold 210 maybe provided with its own motor 133 and electrical generator.

In contrast to frac trailer 110, frac module 210 has a non-rollingchassis 230. Non-rolling chassis 230, however, is similar in manyrespects to rolling chassis 130. Chassis 230 comprises a pair of lateralbeams, such as I-beams 231, which are connected by cross members 232.The primary difference between rolling chassis 130 and non-rollingchassis 230 is that the latter does not incorporate a suspension andwheel assembly. On the other hand, if desired, modular manifold 210 maybe trailer-mounted or have other conventional chassis.

Manifold 210, as noted, is designed to enable a modular approach todesigning and installing frac manifolds for frac systems. Thus, thedesign and dimensions of rolling chassis 130 and non-rolling chassiswill be coordinated to allow missiles 113 and suction lines 182 on fractrailer 110 and modular manifold 210 to be connected in series, that is,end-to-end.

More particularly, modular manifold 210 does not incorporate a suctionmanifold 181. Instead, suction lines 182 may be connected at theirupstream end to the downstream end of suction lines 182 of trailer 110.The connection preferably is made up with flanged spools having the sameinner diameter as suction lines 182. Other conventional flowlinecomponents, however, may be used. In any event, when connected, suctionlines 182 on frac trailer 110 and modular manifold 210 provide a singlepair of joined suction lines 182, one on each side of the combinedmanifold 110/210. Preferably, frac trailer 110 and modular manifold 210will be positioned such that suction lines 182 align axially, allowingthe joined suction lines 182 to extend in a straight line.

The upstream end of missile 113 in frac module 210 is not shut off.Upstream cross junction 120 a of modular module 210 lacks a blind flangeor other closure assembly, such as flush-port assembly 190 incorporatedinto missile 113 of frac trailer 110. Instead, upstream cross junction120 a of modular manifold 210 may be connected to downstream crossjunction 120 f of frac trailer 110. The connection preferably is made upwith flanged spools, such as spools 30, but other conventional flow linecomponents may be used. Preferably, frac trailer 110 and modularmanifold 210 will be positioned such that missiles 113 align axially andjoined missiles 113 extend in a straight line. Cross junction 120 f ofmissile 113 on modular manifold 210 then may be connected to flow line114 running to junction head 115 of zipper manifold 16 as describedfurther below.

In any event, once their respective missiles 113 and suction lines 182are connected, combined manifold 110/210 will be able to service a totalof 24 pumps 10, 12 on each side. Flow through joined suction lines 182,but more importantly, flow through joined missiles 113 will proceed in astraight line. The alignment of joined missiles 113 will tend tomaintain a more laminar flow despite the turbulence introduced by fluidflowing from discharge lines 12 of pumps 10. Equally as important, asingle, or in any event, fewer flow lines and fewer junctions would berequired as compared using two separate conventional frac manifolds.

It also will be appreciated that the novel manifold modules may havegreater or fewer cross junctions allowing them to connect to more orfewer pumps. Likewise, the modules may be used in many differentcombinations to accommodate however many pumps as may be required. Thenovel modules also may incorporate a variety of missiles, includingmultiple missiles, and suction lines. The general design of conventionalmissiles and suction lines in known, and they may be modified to allowthe missiles and suction lines to be connected in series as illustratedabove in respect to combined manifold 110/210.

The novel modular manifolds, as noted, may be mounted on rollingchassis. When they have a non-rolling chassis, such as chassis 230 ofmodular manifold 210, they will be transported to a site on a lowboy,flatbed, or other trailer. They may be loaded on and off the trailer byconventional lifting equipment. Preferably, however, they willincorporate jackup legs allowing them to essentially self-load andself-unload.

For example, as may be seen in FIGS. 17-18, modular manifold 210 isprovided with four hydraulic jackup legs 211. A pair of jackup legs 211is situated toward the front end of manifold 211, one on each side. Theother pair of jackup legs 211 is situated toward the back end ofmanifold 211. Jackup legs 211 are mounted to chassis 230 and may beoperated to elevate and lower chassis 230.

Jackup legs 211 are shown in greater detail in FIG. 19. Missile 113,mounts 140, and many other components of modular manifold 210 have beenremoved from that figure to better show jackup legs 211. As may be seentherein, each jackup leg 211 comprises a vertical lifter 212 connectedto a mount 233. Vertical lifter 212 is of conventional design. It is inessence a hydraulic cylinder and has an outer tube 213 from which aninternal piston or tube 214 may be extended and retracted byconventional hydraulic flow. Internal tube 214 preferably is providedwith a shoe or foot at its lower end, such as pivoting shoe 215.Vertical lifters 212 are connected by lines to conventional hydraulicsystems, and those systems are controlled by conventional controls (notshown).

Mounts 233 are provided on chassis 230. Mounts 233 include an I-beam 234which extends away from I-beams 231. A plate 236 is provided at theother end of I-beams 234. Outer tube 213 of vertical lifter 212 isconnected via a plate 216 to plate 236 of mounts 233. Mounts 233 may beconnected to I-beams 231, and vertical lifters 212 may be connected tomounts 233 by any suitable means, such as welding. Preferably, they areremoveably connected, for example, by bolts or other threadedconnectors. The length of mounts 233 and the length and stroke of innertube 214 are coordinated such that jackup legs 211 may be actuated toallow manifold module 210 to be loaded and unloaded from a trailer.

That is, mounts 233 extend vertical lifters 212 beyond the edges of thetrailer, as may be best appreciated by viewing FIG. 18. When verticallifters 212 are actuated, inner tubes 214 will extend down toward theground a sufficient distance to raise modular manifold 210 above the bedof the trailer. The trailer then may be moved away from under manifold210. Vertical lifters 212 then will be actuated to lower manifold 210,allowing it to rest on the site pad. That procedure may be reversed toload modular manifold 210 on the trailer once operations are completed.It will be appreciated as well that jackup legs 211 may be disassembledfrom modular manifold 210 for transportation to or from a site, and theninstalled when needed.

Jackup legs also may be provided on mounts that allow them to beextended horizontally. For example, modular manifold 210 may be providedwith four horizontally extendable jackup legs 311. Jackup legs 311 areshown in FIG. 20. FIG. 20A shows jackup legs 311 in a fully retractedposition, and FIG. 20B shows them in a fully extended position. As showntherein, jackup legs 311 comprise vertical lifters 211 connected tomounts 333. Mounts 333 comprise a tube 334 and a horizontal extender335. Tube 334 has a generally square cross-section and extendstransversely across chassis 330. It comprises three tube segments whichare mounted to I-beams 331. The tube segments are mounted in alignmentwith each other and with cut-outs (not shown) in I-beams 331. Horizontalextenders 335 are slidably carried within each end of tube 334. Theyhave a plate 336 provided at their outer end. Outer tube 213 of verticallifter 212 is connected via plate 216 to plate 336 of extenders 335. Thesegments of tube 334 may be connected to I-beams 331, and verticallifters 212 may be connected to horizontal extenders 335 by any suitablemeans, such as welding. Preferably, they are removeably connected, forexample, by bolts or other threaded connectors.

In any event, horizontal extenders 335 may be pulled out of tube 334 toextend vertical lifters 212 beyond the edges of a transport trailer.Preferably, mounts 333 will be provided with a mechanism for releasablysecuring extenders 335 within tube 334 in their retracted and in one ormore extended positions. For example, extenders 335 and tube 334 may beprovided with sets of holes which may be aligned by positioningextenders 335, thus allowing extender 335 to be releasably secured totube 334 by pins 337. The length and stroke of horizontal extenders 335and of inner tube 214 are coordinated such that vertical lifters 212 maybe actuated to allow manifold module 210 to be loaded and unloaded froma trailer.

It will be appreciated that suitable jackup legs may have other designsthat allow the modular manifold to be self-loading and self-unloading. Avariety of hydraulic lifters are available from Power-Packer, Inc,Westfield, Wis., and other manufacturers. If desired, horizontalextenders also may be hydraulically driven, and many conventionalhydraulic mechanisms may be adapted for use in the novel modularmanifolds.

While offset cross junctions 120 of missile 113 provide many advantages,it will be appreciated that other junctions accepting feed from two ormore pumps may be incorporated into the novel missiles and fracmanifolds. For example, offset cross junction 220 shown in FIGS. 21-22may be connected to two pumps 10. As seen therein, offset crossjunctions 220 has a somewhat elongated, solid rectangular body 221having a primary bore 222. Bore 222 provides the primary conduit throughwhich slurry passes as it is conveyed towards well head 17. Bore 222extends between opposing flat surfaces or union faces 223 on body 221.

Offset cross junctions 220 also are provided with a pair of bores 226which provide conduits for feeding discharge from an individual pump 10into primary bore 222. Feed bores 226 extend perpendicularly from flatunion faces 227 on body 221 and lead into primary bore 222. Primaryunion faces 223 and feed union faces 227 are substantially identical tounion faces 123 and 127 in offset cross junction 120. They also may beprovided with weep ports (not shown) if desired.

Like cross junction 120, when cross junctions 220 are incorporated intomissile 113 they will have a larger diameter than multiple, smallerflowlines collectively providing comparable flow rates and velocities.The quantity and velocity of particles impinging on the other side ofprimary bore 222 at near normal angles will be less than experienced bysmaller diameter pipes. Feed bores 226 in cross junctions 220 also areoffset axially, as in cross junction 120. Offsetting feed bores 226 willhelp to minimize areas of concentrated turbulence and erosion in crossjunctions 220. Unlike cross junctions 120, however, feed bores 226 incross junctions do not have a long-sweep curve. They are straight-linebores. Thus, the average angle of impact for particles flowing intoprimary bore 222 will be greater, and will tend to cause more erosionthan in cross junction 120.

Offset cross junction 220, however, is a block fitting. That is body 221of junction 200 has a generally polyhedral configuration or, morespecifically an elongated, solid rectangular configuration. As comparedto the tubular fittings from which missiles in conventional fracmanifolds traditionally are assembled, polyhedral bodies, such as solidrectangular and other prismatic bodies, can easily be manufactured toprovide cross junctions 220 with additional thickness in conduit walls.

Preferably the minimum width of body 221 is at least about 3:2, and morepreferably at least about 2:1 or 3:1. Body 221 of cross junction 220 hasa generally square cross section, so its minimum width is the distancebetween opposing sides of body 221. As illustrated, the minimum width ofbody 221 is about 3 times as great as the diameter of primary bore 222.Thus, like cross junctions 120, junctions 220 should be able to toleratemore erosion before reaching a point where the integrity of the fittingis compromised.

Offset lateral cross junction 320 is shown in FIGS. 23-24. Junction 320may be referred to as an offset “lateral” cross junction in that theirfeed bores intersect with the primary bore a shallower angle, ascompared to a tee fitting which intersects more or less normal to theprimary bore. Junctions 320 also may be incorporated into missile 113and connected to two pumps 10. As may be seen in FIGS. 23-24, offsetlateral cross junction 320 has a body 321. The main portion of body 321is polyhedral and, more specifically, has a generally cuboid shape withtrapezoidal prism shaped arms extending from opposite faces. Body 321has a primary bore 322. Bore 322 provides the primary conduit throughwhich slurry passes as it is conveyed towards well head 17. Bore 322extends between opposing flat surfaces or union faces 323 on body 321.

Offset lateral cross junctions 320 also are provided with a pair ofbores 326 which is provide conduits for feeding discharge from anindividual pump 10 into primary bore 322. Bores 326 extendperpendicularly from flat union faces 327 on body 321 and lead intoprimary bore 322. Primary union faces 323 and feed union faces 327 aresubstantially identical to union faces 123 and 127 in offset crossjunction 120. They also may be provided with weep ports (not shown) ifdesired.

It will be noted that bores 326 of offset lateral cross junction 320generally extend toward primary bore 322 at an interior angle, forexample, 45° as shown in FIG. 24. The major portion of bores 326 extendsalong that angle, and feed bores 326 may be deemed to intersect withprimary bore 322 at that angle. As they approach primary bore 322,however, bores 326 are provided with a long-sweep curve having a sweepradius of approximately 7. Bores 326 also intersect with primary bore322 at axially offset junctions. Thus, it is expected that lateral crossjunction 320 will provide further improvements in wear resistance andservice life. Fluid entering primary bore 322 of lateral cross junctions320 from feed bores 326 will not only have more room to spread, but willenter primary bore 322 at a shallower angle. Discharge will be furtherencouraged to flow more along and less across flow in primary conduit322 by the long-sweep curves. Particles impinging on the other side ofprimary bore 322 on average will impact at much shallower angles,further reducing the effects of brittle erosion. Flow through primarybore 322 also will return to laminar flow more quickly.

Consistent therewith, the intersection angle between feed bores 326 andprimary bore 322 may be varied. Preferably, it will be substantiallyless than 90°. Little benefit will be realized at angles near 90°. Morepreferably, the intersection angle will be from about 15° to about 60°.Likewise, the sweep ratio of the curve may be varied. Given that feedbores 326 already approach primary bore 322 at an angle, the sweep ratiowill tend to be somewhat higher than, for example, in feed bores 126 ofcross junctions 120, which approach at right angles to primary bore 122.It also will be appreciated, as compared to the offset between feedbores 126 in offset cross junction 120, feed bores 326 in lateral crossjunction 320 may be offset to a lesser degree. Since fluid is enteringprimary bore 322 at a shallower angle, turbulence in primary bore 322will diminish more rapidly, and assume a more laminar flow than inprimary bore 122 of offset cross junction 120.

Offset lateral cross junction 420 also may be connected to two pumps andused in missile 113 or elsewhere in flow line 100. As may be seen inFIGS. 25-26, offset lateral cross junction 420 is substantiallyidentical to offset lateral cross junction 320 except that feed bores426 in junction 420 do not incorporate a long-sweep curve. It may bemodified and adapted in various respects as can be junction 320.

Right-angle cross junction 520, which is shown in FIGS. 27-28, also maybe incorporated into missile 113 and connected to two pumps 10.Right-angle cross junction 520 has a polyhedral or, more specifically, agenerally cubic body 521. Primary bore 522 extends through body 521 andprovides the primary conduit through which slurry passes as it isconveyed towards well head 17. Bore 522 extends between opposing flatsurfaces or union faces 523 on body 521.

Right-angle cross junctions 520 also are provided with a pair of bores526 which provide conduits for feeding discharge from an individual pump10 into primary bore 522. Bores 526 extend perpendicularly from adjacentflat union faces 527 on body 521 and lead into primary bore 522. Primaryunion faces 523 and feed union faces 527 are substantially identical tounion faces 123 and 127 in offset cross junction 120. They also may beprovided with weep ports (not shown) if desired.

It will be noted that bores 526 in right-angle cross junctions 520 areperpendicular to each other and intersect with primary bore 522 and eachother at right angles. Right-angle cross junctions 520, therefore, maymake it easier to assemble pump discharge lines 12 from pumps 10 oneither side of cross junction 520. Consistent therewith, it will beappreciated that the angle between bores 526 and union faces 527 may bevaried. The a angle may be somewhat greater or lesser than 90° and stillfacilitate connection of pump discharge lines 12 from pumps staged onopposite sides of cross junction 520. Bores 526 also may be offset alongprimary bore 522, similar to offset cross junction 220, may intersectwith primary bore 522 at an angle, similar to offset lateral crossjunction 420, or may incorporate both such features. Similarly, feedbores 526 may incorporate a long-sweep curve, such as is present in feedbores 126 of junction 120 and feed bores 326 of junction 320, to furtherminimize erosion in junction 520.

It will be appreciated that the novel junctions may be modified invarious ways consistent with the invention. For example, offset junction120 and the other exemplified junctions may be provided with a bleederport allowing a pressure relief valve to be assembled to the junction.Flange union faces may be provided around the port to allow the valve ora valve assembly to be joined to the junction by a flange union. A portalso may be provided to allow assembly of a gauge to offset junctions120.

The novel junctions also may incorporate additional feed ports. Offsetjunction 120, for example, may be provided with a third offset feed bore126. Two feed bores 126 may be spaced along one side of body 121,intersecting with primary bore 122 along that side of cross junction120. The third feed bore 126 may be provided on the other side of body121 such that its intersection with primary bore 122 is axially betweenthe intersections of the other two feed bores 126 with primary bore 122.Discharge from the three feed bores 126 will be spaced axially alongprimary bore 122.

Missile 113 will discharge into flow line 114. Flow line 114 is shown inmore detail in FIGS. 10-11. As shown therein, it generally comprises a4-axis swivel joint subassembly 101 having three rotatable elbows 103,additional spools 30, cross junctions 20, valves 51 and 52, a 3-axisswivel joint subassembly 102 having two rotatable elbows 103, and asingle rotatable elbow 103 f. It will be noted that for the sake ofsimplification, FIGS. 10-11 show flow line 114 as connecting to a singlewell head 17 whereas in FIG. 2 flowline is illustrated as feeding intojunction head 115 of zipper manifold 16. In general, the novel flowlines may feed into any conventional wellhead assembly.

Well head 17 comprises a tee connector 60 and a pair of manual gatevalves 51. In accordance with common industry practice, many othercomponents may be assembled into well head 17. Such components also arenot illustrated for the sake of simplicity. It also will be appreciatedthat in the context of novel flow lines which are adapted to deliverfluid from a plurality of pump discharges to a well head, a wellheadassembly will be considered to include such conventional well heads, butalso zipper manifolds and the like which may selectively divert flowinto a plurality of individual well heads.

Flowline segment 114, as illustrated, may incorporate additional orfewer spools 30 of varying lengths running from missile 113 to make upthe distance between frac manifold 110 and well head 17. The novel flowlines also may incorporate other conventional flowline components,units, and subassemblies. For example, flowline segment 114 incorporatescross junctions 20. Cross junctions 20 may be used to allow additionalflowline components or segments to be added, such as pressure reliefvalves or bleed-off lines. The novel flow lines also may incorporate,for example, gauges and other monitoring equipment, as well as controldevices such as shut off, plug, check, throttle, pressure release,butterfly, and choke valves. For example, flow line 114 is provided withvalves 50 and 51. Valve 50 is a conventional manual gate valve. Valve 51is a conventional hydraulic gate valve which may be controlled remotely.

Like missile 113, flowline segment 114 and other novel flow linespreferably will incorporate ports allowing the flow line to be flushedand cleaned out between operations. For example, a flush-port assembly190 may be assembled to a tee junction assembled into flowline segment114 at a desired location. Tee connector 60 in well head 17, forexample, may be replaced with a cross junction 20 having a flush-portassembly 190. The entire flow line 100 thus may be flushed byintroducing clean fluid into missile 113 at cross junction 120 a andallowing it to flow out flush port 190 on well head 17.

Cross junctions 20 are shown in greater detail in FIGS. 29-30. As seentherein, cross junction 20 has a generally cubic body 21 having aprimary bore 22. Bore 22 provides the primary conduit through whichslurry passes as it is conveyed towards well head 17. Bore 22 extendsbetween opposing flat surfaces or union faces 23 on body 21. Crossjunctions 20 also are provided with a pair of bores 26 which provideconduits for feeding fluid from other flow lines into flowline segment114, or for diverting fluid from primary bore 22. Bores 26 extend fromopposing flat union faces 27 on body 21 and lead into and intersect withprimary bore 22. Primary union faces 23 and feed union faces 27 aresubstantially identical to union faces 123 and 127 in offset crossjunction 120.

It will be noted that bores 26 are aligned along their central axes andintersect with primary bore 22 at right angles. Thus, it will beappreciated that cross junctions 20 may be more suitable for divertingflow from a main flow line, such as flow line 114 and as illustrated inFIGS. 10-11. They may be used to connect pumps 10, but opposinghigh-pressure, high-velocity flows, such as the discharge from pumps 10,may create undesirable harmonics in the system and lead to excessivevibration. Feed bores 26, however, may be modified to incorporate along-sweep curve, such as is present in feed bores 126 of junction 120,to reduce such harmonics and to further minimize erosion in junction 20.

Flow lines necessarily must change course as flow is split or combined.Ideally, however, those portions of a flow line extending betweenjunction fittings, would extend in a straight line. Unfortunately, thatrarely, if ever, is possible. For example, as best appreciated fromFIGS. 10-11, in flowline 100, junctions 120 in missile 113 are allaligned and extend in a straight line along they-axis. Junctions 120 andmissile 113, however, are not aligned with well head tee connector 60,which has a union face oriented more or less perpendicular to thex-axis. It also is rarely practical to position pumping units 10, fractrailer 110, and other frac equipment such that they are aligned. Thereis a large amount of equipment at a well site, especially duringfracturing operations. The flow line must be able to accommodatewhatever spatial constraints are present at a site.

Thus, the novel flow lines may incorporate various fittings, such asvarious combinations of novel rotatable elbows 103, to change thedirection or course of the flow line as required for a specific wellsite. For example, as shown in FIGS. 10-11, missile 113 runs straightalong (i.e., parallel to) they-axis between offset cross junction 120 aand offset cross junction 120 f. The heading of flow line 100 may bechanged by incorporating various combinations of rotatable elbows 103.Specifically, 4-axis swivel joint 101, 3-axis swivel joint 102, androtatable elbow 103 f have been used to provide changes in the headingof flow line 100 to accommodate the position of frac manifold 110relative to well head 17.

Swivel joints 101 and 102 comprise, respectively, three and tworotatable elbows 103 assembled together. More specifically, as may beseen in FIGS. 10-11, swivel joint 101 comprises three rotatable elbows103 a, 103 b, and 103 c. Though not fully illustrated in the figures, itwill be appreciated that each rotatable elbow 103 generally comprises abody and two flanges. A central bore makes a long-sweep 90° turn withinthe body between two, mutually perpendicular union faces. The flangesare rotatably mounted on the elbow body on threads extending around thebore openings. The rotatable flanges allow elbows 103 to be made up atthe union faces to each other and to other flowline components by arotatable, flange-type union. The union allows elbows 103 to rotate toany degree relative to an adjacent flowline component before the unionis loaded and fully tightened. Thus, elbows 103 may provide a 90° turnto the left, to the right, or at any angle relative to the adjacentcomponent.

Rotatable elbows 103 are described more fully in applicant's U.S. patentapplication Ser. No. 15/804,353, filed Nov. 6, 2017, the disclosure ofwhich is incorporated herein by reference. It will be noted thatrotatable elbows 103 and swivel joints 101 and 102 shown in FIGS. 10-11are substantially identical, respectively, to rotatable elbows 140 andswivel joints 101 and 102 disclosed in the '353 application. In anyevent, rotatable elbows 103 will allow greater control over the angularalignment of components in a flowline and, therefore, over the direction(or heading) and course (or track) of a flowline.

At the same time, it will be appreciated that other fittings may be usedto change the direction or course of the flow line as required for aspecific well site. For example, various combinations of angled shims,standard spools, and offset spools may be used as described inapplicant's U.S. patent application Ser. No. 15/399,102, filed Jan. 5,2017, the disclosure of which is incorporated herein by reference. Whilethey are more prone to leaking and failure, conventional swivel jointsalso may be used.

The novel flow lines also may be installed within and supported bymodular skid systems. Such systems are described more fully inapplicant's '102 application. It will be appreciated as well that suchmodular systems may incorporate assemblers facilitating the make-up andbreak-down of components mounted on the skids.

The subject invention includes other preferred embodiments which may beused to assemble flow lines. For example, a novel tee junction 620 isshown in FIGS. 31-32. As shown therein, tee junction 620 has a generallycubic body 621 having a primary bore 622. Bore 622 provides the primaryconduit through which slurry passes as it is conveyed through teejunction 620. Bore 622 extends between opposing flat surfaces or unionfaces 623 on body 621. Tee junction 620 also is provided with a bore 626which provides a conduit for feed fluid from other flow lines into, orfor diverting fluid out of primary bore 622. Bore 626 extends from aflat union face 627 on body 621 and leads into and intersects withprimary bore 622. Primary union faces 623 and feed union face 627 aresubstantially identical to union faces 123 and 127 in offset crossjunction 120.

Like bores 126 in offset cross junction 120, feed bore 626 in teejunction 620 is provided with a long-sweep curve leading into primarybore 622. The sweep ratio of bore 626 is approximately 1.33. Byproviding feed bores 627 with a long-sweep curve instead of astraight-line bore, fluid discharged from feed bores 627 will bedirected at an angle more along, and less across the flow of fluidthrough primary bore 622. It will be expected, then, that the averageangle of impact for particles flowing into primary bore 622 will bediminished and, correspondingly, erosion of primary bore 622. Likefitting 120, it also will be appreciated that tee fitting 620 may easilybe manufactured with a cylindrical body.

FIGS. 33-34 illustrate a novel lateral junction 720 which is similar inmany respects to junctions 320 and 620. Lateral junction 720 has agenerally prismatic body 721, what also may be visualized as anelongated solid rectangular body with a prismatic extension off a facethereof. In any event, body 721 has a primary bore 722 which providesthe primary conduit through which slurry passes as it is conveyedthrough lateral junction 720. Bore 722 extends between opposing flatsurfaces or union faces 723 on body 721. Lateral junction 720 also isprovided with a bore 726 which provides a conduit for feed fluid fromother flow lines into, or for diverting fluid out of primary bore 722.Bore 726 extends from a flat union face 727 on body 721 and leads intoand intersects with primary bore 722. Primary union faces 723 and feedunion face 727 are substantially identical to union faces 123 and 127 inoffset cross junction 120.

Like bores 326 in offset lateral cross junction 320, feed bore 726 inlateral junction 720 generally extends toward primary bore 722 at aninterior angle of about 45°. As it approaches primary bore 722, however,bore 726 is provided with a long-sweep curve having a sweep radius ofapproximately 3.5. It may be expected, therefore, that erosion inprimary bore 726 will be reduced.

The flowline components of the subject invention may be manufactured bymethods and from materials commonly used in manufacturing flow ironcomponents. Given the extreme stress and the corrosive and abrasivefluids to which flowline components are exposed, especially thosedesigned for high-pressure, high-velocity flow lines, suitable materialswill be hard and strong. For example, the novel junctions, except fortheir seals, may be manufactured from 4130 and 4140 chromoly steel orfrom somewhat harder, stronger steel such as 4130M7, high end nickelalloys, and stainless steel. The components may be made by any number ofconventional techniques, but typically and in large part will be made byforging, extruding, or mold casting a blank part and then machining therequired features into the part. Conventional components of the novelflow lines are widely available from a number of manufacturers.

The novel junctions also may incorporate spanning and other wear sleevesas disclosed in applicant's '102 application. Such wear sleeves canprovide additional resistance to erosion and wear, especially whenprovided in areas subject to turbulent flow. Wear sleeves also may bereplaced after a period of service, thus avoiding the need to scrap anentire part.

The novel flowline components have been exemplified largely in thecontext of assembling flow lines through flange unions. That is,fittings such as offset cross junction 120, have been exemplified ashaving union faces adapted for connection to another flowline componentby a flange union. If desired, however, other types of unions may beused in the novel flow lines. Flanged hammer union or clamp union subsmay be joined to a block fitting by a flange union, allowing additionalcomponents to be joined by a hammer union or a clamp union. A hammerunion sub or a clamp union sub also may be provided integrally on thenovel fittings if desired, although as noted below, various advantagesmay be gained by assembling the novel flow lines with flange unions.

In general, the novel fittings may be manufactured easily in any of thesizes commonly employed for frac iron. They are not limited to aparticular size. At the same time, however, when manufactured inrelative large sizes with relatively large internal diameters, the novelfittings and flow lines may provide a single, relatively large flowlineover much of the high-pressure side of a frac system. Flow line 100, forexample, runs from pump discharges lines 12 all the way to well head 17.Various advantages may be derived therefrom.

First, the overall layout at a well site is greatly simplified.Simplification of the frac system can create space to access otherportions of the system and reduce confusion among workers at the site.Moreover, by replacing multiple lines with a single line, the totalnumber of components in the system may be reduced. Fewer components meanfewer junctions and fewer potential leak and failure points in thesystem. Fewer components also means less assembly time at a well site.

Second, exposed elastomeric seals are a potential source of leaks. Theyalso increase turbulence through a conduit and, therefore, erosionresulting from the flow of abrasive slurry through the flow line. Thenovel flow lines, however, preferably are assembled using flange unions.Flange unions do not have any exposed elastomeric seals. They haveinternal metal seals situated between the union faces. Thus, preferredfittings, such as offset cross junctions 120, have union faces adaptedfor flange unions, and flow line 100 does not have any exposedelastomeric seals other than those that necessarily may be present incomponents such as control valves.

It will be noted in particular that preferred flow lines, such as flowline 114, are able to accommodate changes in direction withoutconventional directional fittings such as elbows, but especially withoutusing swivel joints. Swivel joints are expensive. They incorporateelastomeric seals and packings. Many also have sharp turns which areparticularly susceptible to erosion. Moreover, they are particularlysusceptible to bending stress caused by vibrations in the flow line.Such strain can lead to failure. In any event, it means that swiveljoints have a relatively shorter service life than many flowlinecomponents. Thus, swivel joints not only are a big component of theoverall cost of a flow line, but they are a primary source of potentialleaks and failure.

The relatively large inner diameter of the novel flowlines such asmissile 113 and flow line 114 can help minimize erosion and failure inother ways. As the diameter of a conduit increases, drag on the fluidpassing through the conduit increases, but not as rapidly as the volumeof fluid. Thus, proportionally there is less drag, and flow through theconduit is more laminar. Moreover, by replacing multiple smaller lineswith a single larger line, overall drag on fluid conveyed through thesystem is reduced. For example, a single 7 1/16 line may replace six 3″lines. The drag through the larger line will be less than half thecumulative drag through the six smaller lines. More importantly, lessdrag means less erosion.

As noted above, the long-sweep curves provided in many embodiments ofthe novel fittings further reduce drag by reducing turbulence at thebore intersections. In this regard, it will be appreciated that optimalsweep ratios may vary from fitting to fitting. In general, largerdiameter feed bores will have smaller sweep ratios than similarly curvedbores with smaller diameters. Low ratios, especially for small diameterbores, will mean a more severe curve which can lead to increased erosionin the feed bore. Higher ratios, regardless of the bore diameter, willdirect fluid more along, and less across flow in the primary bore, butwill necessarily either add to the overall length of the bore or willdiminish the length of the curve. In general, however, for the boresizes typically used in frac iron, it is expected that a sweep ratio offrom about 1.25 to about 8 generally will be preferred. In any event,the more gradual turns provided by various embodiments of the novelfittings will tend to reduce the angle of impingement of abrasiveparticles on the conduit walls and will help reduce brittle erosionthrough the flow line.

In addition, and in accordance with a preferred aspect of the novelsystems, the diameter of novel flowlines will approximate or equal, oreven exceed the inner diameter of the liner extending through thatportion of the well which will be fractured, what is referred to as theproduction liner. Production liners commonly have an inner diameter ofat least about 5 inches. For example, they commonly are assembled with5⅛″ or 7 1/16″ tubulars having, respectively, nominal inner diameters of5.13″ and 7.06″. Thus, the inner diameter of missile 113 and flowline114, for example, may be 7.06″ to match it to the commonly employed 71/16″ production liner. Junction head 115, zipper manifold 16, and wellhead 17 also may be provided with similarly sized inner conduits.Preferably, they will have diameters of at least about 5 inches or atleast about 7 inches. By matching the size of the novel flowlines to thesize of the production liner, backpressure through the system isreduced. It will be possible to provide equivalent flow rates throughthe system, and provide equivalent fracturing pressures in theproduction liner with less pumping pressure at the surface.Consequently, it may be possible to reduce the number of pumps requiredfor a particular frac job. In any event, the pumps may be operated atlower pressures, minimizing wear and tear on those units.

Perhaps most importantly, the relatively large diameter of the novelflow lines, such as flow line 100, along with their relatively straightcourse and, where necessary, more gradual turns may create theopportunity for on-site inspection. That is, there are variousconventional systems which allow inspection of the inside of pipelinesused to transport oil and gas. Such pipelines typically have largerinternal diameters and fewer turns, especially sharp turns, than arepresent in conventional frac systems. Such in-line inspection (ILI)systems include cameras which are deployed into a conduit to visuallyinspect the internal walls for defects. The capabilities of visual ILIsystems may be enhanced by using penetrating dyes. Magnetic-fluxleakage, magnetic particle, and electromagnetic acoustic transducer ILIsystems also may be deployed to detect electromagnetic anomalies causedby corrosion and erosion. Pit gauges, calipers, or 3-D laser (LIDAR)systems also may be deployed to map the surface of the conduit.

Many of those systems and techniques are used to inspect components atoff-site production or certification facilities. The flow linestypically will be disassembled and their individual componentsinspected. The use of conventional ILI systems on site, however, isextremely limited or nonexistent in conventional flow lines used in fracsystems. Conventional frac systems typically employ too many relativelysmall flow lines having a relatively high number of relatively sharpturns. It is difficult or impossible to run conventional ILI equipmentthrough much, if not all of the system.

By using a single, relatively large flow line with more gradual bends,however, various embodiments of the invention make such in-lineinspection techniques possible. For example, flow line 100 has a single,relatively large diameter flow line running all the way from dischargelines 12 of pumps 10, that is, from and including missile 113 to wellhead 17. Flow line 100 preferably will be made up of components having aconduit of at least about 5 inches in diameter. Typically, thecomponents will have conduits having about 5 or about 7-inch diameters.Missile 113 runs straight. The bends in flow line 114 between crossjunction 120 f and well head 17 also are gradual. There are no sharp 90°turns. Even where directional fittings, such as rotatable elbows 103,are provided with intersecting bores instead of long sweep bores, theirconduits will still be relatively large.

Thus, many conventional in-line inspections systems may be run into flowline 100 as assembled at a well site—without necessarily returning to amaintenance facility. For example, flush-port assembly 190 may bedisassembled from cross junction 120 a, allowing an ILI tool to beplaced in missile 113 of frac trailer 110. The ILI tool then may be runthrough missile 113, into missile 113 of manifold module 210, and thenthrough flowline 114, all without disassembly and while in service at awell site. Missiles 113 of frac trailer 110 and manifold module 210 maybe inspected at a maintenance site before and after deployment withoutany significant disassembly. Thus, it may be expected that the novelflow lines will have significantly reduced maintenance costs.

It also will be appreciated that debris and other contaminants leftbehind in flow lines can interfere with many ILI systems. For example,visual inspections conducted by running cameras through flow line 100require that the inner surfaces of the conduit be relatively clean. Itwill be appreciated that providing flush ports, such as flush-portassembly 190, will allow cleaning of flow line 100 without disassemblyallowing, in turn, inspection of flow line 100 without disassembly.

Similarly, the novel flow lines and components have been described inthe context of frac systems. While frac systems in particular and theoil and gas industry in general rely on temporary flow lines, the novelflow lines and components are not limited to such applications orindustries. Suffice it to say that the novel flow lines and componentshave wide applicability in those fluid transportation systems wheretemporary flow lines have been conventionally applied.

While this invention has been disclosed and discussed primarily in termsof specific embodiments thereof, it is not intended to be limitedthereto. Other modifications and embodiments will be apparent to theworker in the art.

What is claimed is:
 1. A fluid transportation system for fracturing awell, said system comprising: (a) a missile adapted to manifold thedischarge from a plurality of pumps; (b) a flow line connected to saidmissile; (c) a wellhead assembly connected to said flowline, and (d) aproduction liner extending into said well and in fluid communicationwith said wellhead assembly; (e) wherein the inner diameter of saidmissile and said flow line have diameters about equal to or greater thanthe inner diameter of said liner.
 2. The frac system of claim 1, whereinsaid inner diameter of said liner is about equal to or greater than atleast about 5 inches or at least about 7 inches.
 3. A frac manifoldcomprising: (a) a frame; and (b) a missile adapted to manifold thedischarge from a plurality of pumps and comprising cylindrical portions;(c) wherein said missile is mounted to said frame by a plurality ofmounts, said missile being coupled to said mounts and said mounts beingcoupled to said frame; (d) wherein said mounts each comprise a pedestalcoupled to said frame and a cradle supported on said pedestal; (e)wherein said missile is received in and coupled to said cradle at saidcylindrical portions.
 4. The frac manifold of claim 3, wherein: (a) saidmissile comprises a single missile; (b) said frame comprises two beamsextending generally parallel to said missile and joined bycross-members; and (c) said pedestals are coupled to both said beams. 5.The frac manifold of claim 4, wherein each pedestal comprises a basecoupled to said beams and a standard supporting said cradle, saidstandard extending across said base and at least partially across saidbeams.
 6. The frac manifold of claim 3, wherein said missile comprisesjunction fittings having a generally cylindrical body and the length ofsaid cradle is at least about 50% of the length of said junctionfittings.
 7. The frac manifold of claim 3, wherein said missilecomprises junction fittings having a generally cylindrical body and thelength of said cradle is at least about 80% of the length of saidjunction fittings.
 8. A frac manifold module, said manifold modulecomprising a frame supporting: (a) a missile mounted on said frame andadapted to manifold the discharge from a plurality of pumps; and (b) atleast two suction lines mounted on said frame, each said suction linebeing adapted to distribute flow to at least one of said plurality ofpumps; (c) wherein said module lacks a suction manifold distributingflow to said suction lines.
 9. The manifold module of claim 8, whereinsaid missile: (a) is adapted for connection at its downstream end to aflow line or to a missile on a first other frac manifold; and (b) isadapted for connection at its upstream end to a missile on a secondother manifold.
 10. The manifold module of claim 8, wherein said framecomprises a plurality of vertically adjustable, jackup legs adapted toraise and lower said frame.
 11. The manifold module of claim 10, whereinsaid jackup legs comprise a vertical lifter.
 12. The manifold module ofclaim 11, wherein said vertical lifter is attached to a horizontalextender.
 13. The manifold module of claim 8, wherein said suctionlines: (a) are adapted for connection at their downstream ends tosuction lines on a first other frac manifold; and (b) are adapted forconnection at their upstream end to suction lines on a second other fracmanifold.
 14. A frac manifold system, said manifold system comprising afirst and second manifold module, wherein: (a) said first manifoldmodule is the manifold module of claim 8 and said missile is a singlemissile a straight flow line adapted to manifold the discharge from afirst plurality of pumps; and (b) said second manifold comprises: i) aframe; and ii) a single missile providing a straight flow line adaptedto manifold the discharge from a second plurality of pumps; (c) whereinsaid missile on said first module is joined to said missile on saidsecond module.
 15. The manifold system of claim 14; wherein saidmissiles on said first and second modules are aligned to provide astraight flow line.
 16. The manifold system of claim 14, wherein: (a)said second module comprises a pair of suction lines and a suctionmanifold adapted to distribute flow to said suction lines; and (b)wherein said suction lines on said first module are connected to saidsuction lines on said second module.
 17. The manifold system of claim14, wherein at least one of said manifold modules comprises levelersadapted to align said missiles.
 18. The manifold system of claim 14,wherein at least one of said manifold modules comprises a plurality ofvertically adjustable, jackup legs adapted to raise and lower saidmanifold module.
 19. The frac manifold of claim 18, wherein said jackuplegs comprise a vertical lifter.
 20. The frac manifold of claim 19,wherein said vertical lifter is attached to a horizontal extender.
 21. Aflowline assembly mounted on a frame, said assembly comprising: (a) aflow line comprising a plurality of components joined by unions along acommon axis, said unions allowing said components to be made up andbroken down; (b) said components being releasably coupled to said frameto restrict movement along said axis and, when released, adapted totranslate relative to said frame along said axis; (c) a shifter adaptedfor selective coupling to said components and for movement relative tosaid frame along said axis; (d) wherein said shifter may be actuated toshift a first said component relative to a second said component alongsaid axis by: i) uncoupling said first component from said frame andcoupling said first component to said shifter; and ii) actuating saidshifter.
 22. The flowline assembly of claim 21, wherein said flow lineis a missile and said components comprise cross junction fittings. 23.The flowline assembly of claim 21, wherein said components are coupledto said frame by a mount, said components being fixedly coupled to saidmount and said mount being releasably coupled to said frame, and whereinsaid shifter and said mount may be selectively coupled.
 24. The flowlineassembly of claim 23, wherein said mount comprises a pedestal releasablycoupled to said frame and a cradle adapted to receive said component.25. The flowline assembly of claim 23, wherein said frame has two beamsextending generally parallel to said axis and joined by cross-membersand said mount is releasably coupled to said beams and is adapted toslide along said beams when said shifter is actuated.
 26. The flowlineassembly of claim 23, wherein said assembly comprises a bearing elementdisposed between said mount and said frame.
 27. The flowline assembly ofclaim 21, wherein said assembly comprises a hydraulic cylinder coupledto said shifter.
 28. A method of breaking down a flow line with ashifter mounted on a frame; wherein: (a) said flow line comprises aplurality of components joined by unions along a common axis, (b) saidunions allow said components to be made up and broken down; and (c) saidcomponents are releasably coupled to said frame to restrict movementalong said axis and, when released, adapted to translate relative tosaid frame along said axis; and (d) said method comprises: i) enjoininga first said component from a second said component; ii) uncoupling saidsecond component from said frame; and iii) actuating said shifter tomove said second component on said frame along said axis away from saidfirst component.
 29. A method of making up a flow line with a shiftermounted on a frame; wherein: (a) said flow line comprises a plurality ofcomponents joined by unions along a common axis, (b) said unions allowsaid components to be made up and broken down; and (c) said componentsare releasably coupled to said frame to restrict movement along saidaxis and, when released, adapted to translate relative to said framealong said axis; and (d) said method comprises: i) placing a first saidcomponent and a second said component on said frame; ii) actuating saidshifter to move said second component on said frame along said axistoward said first component; and iii) joining said first component andsaid second component.